Guidelines for Authors

Thank you for your interest in Chinese Clinical Oncology (CCO; Chin Clin Oncol; Print ISSN 2304-3865; Online ISSN 2304-3873). CCO adheres to the ICMJE’s Recommendations for the Conduct, Reporting, Editing, and Publication of Scholarly work in Medical Journals (1), COPE’s Code of Conduct and Best Practice Guidelines for Journal Editors (2), and WAME’s policy (3) for generating this author instruction. Please refer to the following guidelines to help you prepare your manuscript. Feel free to contact the editorial office by email (editor@thecco.net) should you have any questions. To ensure a swift peer review and publication process, manuscripts that do not adhere to the following instructions will be returned to the corresponding author for technical revision at the preliminary review. The author instruction is updated on September 02, 2024.

1. ABOUT THE JOURNAL

The Chinese Clinical Oncology (CCO; Chin Clin Oncol; Print ISSN 2304-3865; Online ISSN 2304-3873) is an Open Access, peer-reviewed, bimonthly journal (quarterly published from Sep 2012-Dec 2015). It has been indexed in MEDLINE/PubMed since 2014 and Emerging Sources Citation Index (ESCI) since 2016, and has attained its latest impact factor of 2.1 for the year 2023. CCO publishes original articles, editorials, technical notes, case reports and reviews. The main focus of the journal is to describe new findings in the field of oncology and to provide current and practical information on diagnosis, prevention and clinical investigations of cancer. Specific areas of interest include, but are not limited to, multimodality therapy, markers, imaging, tumor biology, pathology, chemoprevention and technical advances related to cancer.

CCO is the official journal of the Society of Translational Medicine (STM).

For more about our journal, please see: https://cco.amegroups.org/about

2. MANUSCRIPT CATEGORIES

Manuscript categories	Word limit	Abstract	Key words	Main text	Reference	Tables and Figures	Structure template
Original Article	No limit	Structured with Background, Methods, Results, and Conclusions; 200–450 words	3–5	Structured as Introduction, Methods, Results, Discussion, and Conclusions; Require a highlight box	No limit	No limit	Download
Review Article	6,000 max.	Unstructured, except for some certain types; 200–350 words	3–5	Include Introduction, main body* (require discussing on strengths and limitations of the review), and Conclusions	No limit	No limit	Download
-Systematic Review	6,000 max.	Structured with Background, Methods, Results, and Conclusions; 200–350 words	3–5	Structured as Introduction, Methods, Results, Discussion, and Conclusions; Require a highlight box	No limit	No limit	Download
-Scoping Review	6,000 max.	Structured with Background, Methods, Results, and Conclusions; 200–350 words	3–5	Structured as Introduction, Methods, Results, Discussion, and Conclusions; Require a highlight box	No limit	No limit	Download
-Narrative/Literature Review	6,000 max.	Structured with Background and Objective, Methods, Key Content and Findings, and Conclusions; 200–350 words	3–5	Include Introduction, Methods, main body*, and Conclusions.	No limit	No limit	Download
-Clinical Practice Review	6,000 max.	Unstructured; 200–350 words	3–5	Structured as Introduction, main body*, and Conclusions.	No limit	No limit	Download
-Mini-Review	3,000 max.	Unstructured; 200–350 words	3–5	Unstructured	30 max.	3 max.	NA
Clinical Practice Guideline	No limit	Structured with Background, Methods, Results, and Conclusions; 200–350 words	3–5	Include Introduction, Methods, main body* (Contain clear recommendations and discussions), and Conclusions; Require a highlight box	No limit	No limit	Download
Expert Consensus	No limit	Structured with Background, Methods, Results, and Conclusions; 200–350 words	3–5	Include Introduction, Methods, main body* (Contain clear recommendations and discussions), and Conclusions; Require a highlight box	No limit	No limit	Download
Case Series	2,500 max.	Structured with Background, Case Description, and Conclusions; 200–350 words	3–5	Structured as Introduction, Case Presentation, Discussion, and Conclusions; Require a highlight box	35 max.	8 max.	Download
Case Report	2,500 max.	Structured with Background, Case Description, and Conclusions; 200–350 words	3–5	Structured as Introduction, Case Presentation, Discussion, and Conclusions; Require a highlight box	35 max.	8 max.	Download
Case Report: iMDT Corner	6,000 max.	Structured with Background, Case Description, and Conclusions; 200–350 words	3–5	Structured as Introduction, Case Presentation, Discussion, and Conclusions; Require a highlight box	35 max.	8 max.	Download
Surgical Technique	5,500 max.	Unstructured; 200–350 words	3–5	Structured as Introduction, Preoperative Preparations and Requirements, Step-by-step Description, Postoperative Considerations and Tasks, Tips and Pearls, Discussion, and Conclusions; Require a highlight box	No limit	No limit	Download
Brief Report	2,500 max.	Unstructured; 200–350 words	3–5	Unstructured	35 max.	8 max.	NA
Images in Clinical Medicine	No limit	Not required	Not required	Unstructured	10 max.	8 max.	NA
Study Protocol	No limit	Structured as Background, Methods, Discussion, and Registration; 200–350 words	3–5	Structured as Introduction, Methods, and Discussion.	No limit	No limit	Download
Editorial	2,500 max.	Not required	3–5	Unstructured	No limit	2 max.	NA
Editorial Commentary	2,500 max.	Not required	3–5	Unstructured	25 max.	2 max.	NA
Letter to the Editor	1,000 max.	Not required	Not required	Unstructured	10 max.	1 max.	NA

*The word “main body” should not be used as a subheading and authors are free to decide on the subheadings for the content of the main body.

2.1 Original Article
Original articles are articles that report the results of original research investigations. Original articles must have originality and clinical impact.
Word limit: there is no fixed word limit for research articles, but authors must use the most concise language possible, as well as succinct, structured sentences. The word count for the main text (excluding the abstract, references, tables, boxes, or figures) should be provided when the manuscript is submitted.
Abstract: 200–450 words structured with the subheadings Background, Methods, Results, and Conclusions.
Keywords: 3–5.
Main text: Original articles should organize the main text in Introduction, Methods, Results, Discussion, and Conclusions. In addition, original articles are required to contain a box that highlights the key findings and potential impacts. See the “Main Text” section for details.
References: No limit.
Figures/Tables: No limit, but 10 figures are deemed sufficient.
Contributions: Original articles should include a section describing the contribution made by each author to the manuscript. See the “Author Contributions” section for details.
Data Sharing Statement: If a submitted article includes any data that are not publicly available, the authors are required to fill in a data-sharing statement form, which should be submitted along with their manuscript. If the article is accepted for publication, the Data Availability Statement (form) will be published online alongside the article. See the “Data Sharing Statement” section for details.
Ethical Statement: When a manuscript documents any experiment(s) involving human subjects or animals, the authors must indicate an ethical statement both in the methods section and the footnote. See the “Ethical Statement” section for details.

Please note that only a systematic review with meta-analysis will be categorized as an Original Article while a systematic review without meta-analysis will be categorized as a Review Article. Besides, for articles that use data from patients, when the number of patients in the article is ≤3, the article will be classified as Case Report; when the number of patients in the article is between 4 and 9, the article will be classified as Case Series; when the number of patients in the article is ≥10 and the article contain statistical analysis, the article will be classified as Original Article (the article format should refer to Original Article).

2.1.1 Reporting Checklist
Apart from following the general format as indicated above, Original Articles should be prepared according to the EQUATOR research reporting guidelines (4), as some commonly used guidelines listed below, and each submission should include a checklist (a reformatted version has been created for the journal) as supplementary material. The relevant page/line and section/paragraph number in the manuscript should be stated for each item in the checklist. A statement should be included at the end of the “Introduction” to indicate which reporting checklist was followed (e.g., “We present this article in accordance with the CONSORT reporting checklist.”). The manuscript should also include a Reporting Checklist statement in the footnote (see the “Footnote” section). Failure to do so will result in the manuscript being returned to the authors for amendment. Please note that the application of a checklist is aimed at transparent and clear reporting to allow a better critical appraisal of the manuscript. The final format of the manuscript should follow the author instruction requirements.

Study Type	Guideline*	Download Checklist (reformatted for the journal)
Randomized controlled trial	CONSORT (CONsolidated Standards Of Reporting Trials) (5)	CONSORT Checklist
Nonrandomized design	TREND (Transparent Reporting of Evaluations with Nonrandomized Designs) (6)	TREND Checklist
Observational studies in Epidemiology	STROBE (STrengthening the Reporting of Observational studies in Epidemiology) (7)	STROBE Checklist
Diagnostic accuracy study	STARD (STAndards for Reporting of Diagnostic Accuracy Studies) (8)	STARD Checklist
Systematic review or meta-analysis	PRISMA (Preferred Reporting Items for Systematic Reviews and Meta-Analyses) (9)	PRISMA Checklist
Animal research	ARRIVE Guidelines (10)	ARRIVE Checklist
Prediction Model Development and Validation	TRIPOD Guidelines (11)	TRIPOD Checklist

*Authors may refer to the Extensions to the CONSORT Statement based on the specific study type; if a particular study type has not been included in the above list, authors can find more reporting guidelines on EQUATOR Network (https://www.equator-network.org/home/) (4) and should indicate upon submission which guideline has been followed and provide related reporting checklist if available.

2.1.2 Selection and Description of Participants
In study articles, the process of selection for observational or experimental subjects (healthy individuals or patients, including controls) should be clearly set out in the methods section. Any eligibility or exclusion criteria should be provided, along with a description of the population from which the subjects were sourced. Ideally, representative populations should be included in all study types, and characteristics (such as age, sex, or ethnicity) of the study population should be described. Terms relating to sex (when reporting biological factors) and gender (identity, psychosocial or cultural factors) should be used correctly, and the sex and/or gender of the human participants, or the sex of animals or cells, should be reported, except where this is not appropriate. The methods used to classify sex and gender should also be described, where relevant. If the study focused on a specific population, for example in only one sex, the authors should explain their reasoning for this. For race and ethnicity, authors should describe how these were determined, and their relevance to the study should be explained. Study subjects should be described in the most neutral, exact, and respectful language possible. Any language that might cause the stigmatization of subjects must be avoided.

Authors are encouraged to refer to the SAGER guidelines for reporting of sex and gender information in study design, data analyses, results, and interpretation of findings: www.equator-network.org/reporting-guidelines/sager-guidelines/ (12).

2.1.3 Research Resource Identifiers (RRID)
CCO is pleased to be a part of the Research Resource Identification Initiative (13), a project aimed at clearly identifying key research resources used in the course of scientific experiments. These include antibodies, cell lines, model organisms, and software tools. To help authors quickly find the correct identifiers for their materials there is a single website (https://scicrunch.org/resources) (13) where all resource types can be found and a 'cite this' button next to each resource that contains proper citation text that should be included in the methods section of the manuscript. Several examples of properly formatted methods sections with RRIDs can be found below:

• Antibodies: "antibody against ERK1 (Abgent Cat# AP7251E, RRID: AB_2140114)."
• Cell Lines: "we used the following cell lines: RRID: CVCL_1H60,..."
• Genetically modified organisms: "Fgf9Eks/Fgf9+ mice (RRID: MGI_3840442)..."
• Software tools: "...terminals were mapped (Neurolucida, v10, RRID: SCR_001775)."

2.2 Review Article
Review articles are articles that identify, synthesize and summarize existing evidence and information on a specific topic. Review articles should present a timely, comprehensive analysis of a specific topic. We welcome the submission of proposals for review articles for initial consideration.
Word limit: 6,000 words max, including abstract but excluding references, tables, and figures.
Abstract: 200–350 words. Unstructured, except for certain types of reviews, e.g., systematic reviews without meta-analysis, scoping reviews, and narrative reviews.
Keywords: 3–5.
Main text: Include Introduction, main body (the word “main body” should not be used as a subheading and authors are free to decide on the subheadings for the content of the main body), and Conclusions. Some reviews require a Methods section, such as systematic reviews, scoping reviews, and narrative/ literature reviews. It is important to note that we require that the main body of a review also contain a discussion on the main strengths and limitations to inform the reader of a more objective understanding of the information in the review. In addition, systematic reviews and scoping reviews are required to contain a box that highlights the key findings and potential impacts. See the “Main Text” section for details.
References: No limit, except for mini-reviews.
Figures/Tables: No limit, except for mini-reviews.
Contributions: Review articles should include a section describing the contribution made by each author to the manuscript. See the “Author Contributions” section for details.
Ethical Statement: When a review documents any image(s) or video(s) involving human subjects or animals, the authors must indicate an ethical statement both in the methods section and the footnote. See the “Ethical Statement” section for details.

Besides the conventional review article, there are some typical classifications of review articles listed below, which may entail the conformation with a reporting guideline.

2.2.1 Systematic Reviews without Meta-analysis
We strongly welcome the submission of systematic reviews. A systematic review consists of searching, screening, and selecting all eligible literature following predetermined eligibility criteria, and appraising and synthesizing the literature to answer a specific research question. A systematic review requires a rigorous and systematic approach to reduce bias and produce more trusted evidence to facilitate decision-making (https://www.cochranelibrary.com/about/about-cochrane-reviews) (14). Systematic reviews without meta-analysis are categorized as Review Articles.

In addition to following the general format of a review article described above, this type of review should also adhere to the PRISMA (Preferred Reporting Items for Systematic Reviews and Meta-Analyses) (9) and each submission should include the PRISMA Checklist (a reformatted version has been created for the journal can be downloaded here) as a supplementary material. The relevant page/line and section/paragraph number in the manuscript should be stated for each item in the checklist. The statement “We present this article in accordance with the PRISMA reporting checklist” should be included at the end of the “Introduction”. The manuscript should also include a Reporting Checklist statement in the footnote (see the “Footnote” section). Failure to do so will result in the manuscript being returned to the authors for amendment. Please note that the application of a checklist is aimed at transparent and clear reporting to allow a better critical appraisal of the manuscript. The final format of the manuscript should follow the author instruction requirements.

Abstract: Structured with Background, Methods, Results, and Conclusions.
Main text: Arranged as Introduction, Methods, Results, Discussion, and Conclusions. Systematic reviews are required to contain a box that highlights the key findings and potential impacts. See the “Main Text” section for details.

2.2.2 Scoping Review
We strongly welcome the submission of scoping reviews. Similar to a systematic review, a scoping review also contains systematic literature searching, screening, and selecting. However, it differs in not requiring a quality appraisal of the included literature. The report of a scoping review should follow the PRISMA-ScR (Preferred Reporting Items for Systematic Reviews and Meta-Analyses extension for Scoping Reviews) (15) Checklist and each submission should include the PRISMA-ScR Checklist (which can be downloaded here) as supplementary material. The relevant page/line and section/paragraph number in the manuscript should be stated for each item in the checklist. The statement “We present this article in accordance with the PRISMA-ScR reporting checklist” should be included at the end of the “Introduction”. The manuscript should also include a Reporting Checklist statement in the footnote (see the “Footnote” section). Failure to do so will result in the manuscript being returned to the authors for amendment. Please note that the application of a checklist is aimed at transparent and clear reporting to allow a better critical appraisal of the manuscript. The final format of the manuscript should follow the author instruction requirements.

Abstract: Structured with Background, Methods, Results, and Conclusions.
Main text: Arranged as Introduction, Methods, Results, Discussion, and Conclusions. Scoping reviews are required to contain a box that highlights the key findings and potential impacts. See the “Main Text” section for details.

2.2.3 Narrative Review (Also Called Literature Review)
We strongly welcome the submission of narrative reviews, although our editors may still consider traditional reviews for publication. A narrative review aims to provide readers with cutting-edge, scholarly, evolving developments and evidence-based overview of a clinical or mechanistic subject by searching, selecting, compiling, and summarizing the available literature. Through a narrative review, readers could gain more comprehensive and enlightening knowledge on a particular field. A narrative review is less methodologically demanding than a systematic review, as it does not require a search of all literature in a field, nor does it necessarily require a rigorous appraisal of the included literature.

Abstract: Structured with

• Background and Objective: describe relevant background, reasons for conducting this review, and primary objectives of this review.
• Methods: briefly describe the search strategy, including databases, time frame, and language considerations.
• Key Content and Findings: describe what the literature review will mainly contain and any key findings.
• Conclusions: describe the main conclusions and how the review may potentially impact future research, clinical practice, and policy making.

Main text: Arranged as Introduction, Methods, main body (the word “main body” should not be used as a subheading and authors are free to decide on the subheadings for content of the main body) and Conclusions. The Methods section should include a completed table as follows:

Table X. The search strategy summary

Items	Specification
Date of search (specified to date, month and year)
Databases and other sources searched
Search terms used (including MeSH and free text search terms and filters) Note: please use an independent supplement table to present detailed search strategy of one database as an example
Timeframe
Inclusion and exclusion criteria (study type, language restrictions etc.)
Selection process (who conducted the selection, whether it was conducted independently, how consensus was obtained, etc.)
Any additional considerations, if applicable

Note: Please note that a narrative review is less methodologically demanding than a systematic review, as it does not require a search of all literature in a field. Therefore, the search strategy summary of a narrative review is mainly used for more transparent reporting.

In addition to following the general format of a review article described above, narrative reviews should also adhere to the narrative review checklist (available here) and each submission should include the Checklist as supplementary material. The relevant page/line and section/paragraph number in the manuscript should be stated for each item in the checklist. The statement “We present this article in accordance with the narrative review reporting checklist” should be included at the end of the “Introduction”. The manuscript should also include a Reporting Checklist statement in the footnote (see the “Footnote” section). Failure to do so will result in the manuscript being returned to the authors for amendment. Please note that the application of a checklist is aimed at transparent and clear reporting to allow a better critical appraisal of the manuscript. The final format of the manuscript should follow the author instruction requirements.

2.2.4 Clinical Practice Review
A clinical practice review is often shorter than a systematic review, a scoping review, or a narrative review. It mainly provides a summary of clinical issues involving clinical manifestations, diagnosis, treatment, prognosis, etc. It often requires perspective and expert opinion along with evidence-based review and may include early or unpublished observations. For example, it can be a detailed step-by-step and empirical summary of certain surgical techniques or approaches; it can be a comparative summary of several treatment approaches; it can also be a review of a controversial clinical issue to sort out the controversy and the possible best approach, and so forth.

Abstract: Unstructured within 200–350 words.
Main text: Include Introduction, main body (the word “main body” should not be used as a subheading and authors are free to decide on the subheadings for the content of the main body), and Conclusions.

2.2.5 Mini-Review
A mini-review often provides a fairly brief summary of experience, literature, techniques, or other issues. Though a mini-review is far less comprehensive than a systematic review, scoping review, narrative review, or clinical practice review, it is concise with minimal text to target valuable topics or emerging topics that have not yet been extensively researched.

Word limit: 3,000 words max, excluding abstract, references, tables, and figures.
Abstract: Unstructured within 200–350 words.
Main text: Unstructured.
References: 30 max.
Figures/Tables: 3 max.

2.3 Clinical Practice Guideline and Expert Consensus

2.3.1 Clinical Practice Guideline
The clinical practice guidelines are recommendations that provide the optimum care for patients based on evidence from systematic reviews and a balance of the benefits and harms of different interventions. Ideally, a Clinical Practice Guideline should follow a methodical rigorous approach to its development, including, protocol drafting and registration (e.g., http://www.guidelines-registry.org) (16), clear screening and identification of clinical concerns, systematic search of existing similar guidelines, systematic searching, evaluating and grading of evidence, and management of conflicts of interest of participants, and strict consensus methods for forming recommendations, etc.

Word limit: There is no fixed word limit for clinical practice guidelines but authors must use the most concise language possible, as well as succinct, structured sentences. The word count for the main text (excluding the abstract, references, tables, boxes, or figures) should be provided when the manuscript is submitted.
Abstract: 200–350 words structured with the subheadings Background, Methods, Results, and Conclusions.
Keywords: 3–5.
Main text: Clinical practice guidelines should organize the main text in the Introduction, Methods, and main body (Contain clear recommendations and discussions; the word “main body” should not be used as a subheading and authors are free to decide on the subheadings for the content of the main body) and Conclusions. In addition, clinical practice guidelines are required to contain a box that highlights the key recommendations. See the “Main Text” section for details.
References: No limit.
Figures/Tables: No limit.
Contributions: Clinical practice guidelines should include a section describing the contribution made by each author to the manuscript. See the “Author Contributions” section for details.
Ethical Statement: When a manuscript documents any experiment(s) involving human subjects or animals, the authors must indicate an ethical statement both in the methods section and the footnote. See the “Ethical Statement” section for details.

In addition to following the general format of a clinical practice guideline described above, this type of article should also adhere to the RIGHT (Reporting Items for Practice Guidelines in Healthcare) (17) and each submission should include the RIGHT Checklist (a reformatted version has been created for the journal can be downloaded here) as a supplementary material. The relevant page/line and section/paragraph number in the manuscript should be stated for each item in the checklist. The statement “We present this article in accordance with the RIGHT reporting checklist” should be included at the end of the “Introduction”. The manuscript should also include a Reporting Checklist statement in the footnote (see the “Footnote” section). Failure to do so will result in the manuscript being returned to the authors for amendment. Please note that the application of a checklist is aimed at transparent and clear reporting to allow a better critical appraisal of the manuscript. The final format of the manuscript should follow the author instruction requirements.

2.3.2 Expert Consensus
Expert consensus is a way to generate key clinical questions, determine the best evidence, and form recommendations. When expert consensus appears as a category of articles, it is similar to clinical practice guidelines in that it requires expert assessment and comprehensive judgment of the quality and credibility of the evidence.

Expert consensus differs from clinical practice guidelines in that, it is not necessarily developed by professional societies and associations, as clinical guidelines are, but also by experts with certain influence in a particular field; it tends to be developed in a shorter period of time; the development process tends to be less scientifically rigorous than that of clinical practice guidelines; there may or may not be a grading of the evidence; and the quality of the evidence included is often not as high as in clinical practice guidelines, etc.

Word limit: There is no fixed word limit for expert consensus but authors must use the most concise language possible, as well as succinct, structured sentences. The word count for the main text (excluding the abstract, references, tables, boxes, or figures) should be provided when the manuscript is submitted.
Abstract: 200–350 words structured with the subheadings Background, Methods, Results, and Conclusions.
Keywords: 3–5.
Main text: Expert consensus should organize the main text in the Introduction, Methods, and main body (Contain clear recommendations and discussions; the word “main body” should not be used as a subheading and authors are free to decide on the subheadings for the content of the main body) and Conclusions. In addition, an expert consensus is required to contain a box that highlights the key recommendations. See the “Main Text” section for details.
References: No limit.
Figures/Tables: No limit.
Contributions: Expert consensus should include a section describing the contribution made by each author to the manuscript. See the “Author Contributions” section for details.
Ethical Statement: When a manuscript documents any experiment(s) involving human subjects or animals, the authors must indicate an ethical statement both in the methods section and the footnote. See the “Ethical Statement” section for details.

2.4 Case Series
Case Series is an article reporting observations of diseases, clinical findings, or novel/unique treatment outcomes that are relevant to several participants/patients in related fields. Only cases of exceptional interest and novelty are considered. Of note, only when the number of patients in the article is between 4 and 9, the article will be classified as Case Series. Otherwise, the article will be classified as a Case Report (the number of patients is≤3) or an Original Article (when the number of patients is ≥10 and the article contain statistical analysis).

Word limit: 2,500 words max. (excluding references, tables, and figures)
Abstract: 200–350 words max. Structured with:

• Background: state what is known and unknown; why the case report is unique and what it adds to existing literature.
• Case Description: describe the patient’s demographic details and main history, the main diagnosis, interventions, outcomes, and follow-ups.
• Conclusions: summarize the main take-away lesson, clinical impact, and potential implications.

Keywords: 3–5.
Main text: The text should be arranged as Introduction, Case Presentation, Discussion, and Conclusions. In addition, case reports and case series are required to contain a box that highlights the key findings and potential impacts. See the “Main Text” section for details.
References: 35 max.
Figures/Tables: 8 max. (combined)
Contributions: The case series should include a section describing the contribution made by each author to the manuscript. See the “Author Contributions” section for details.
Ethical Statement: The case series should include an ethical statement indicating whether written consent has been obtained from the subject (or their parent/guardian). See the “Ethical Statement” section for details.

2.4.1 Reporting Checklist
Apart from following the general format as indicated above, authors should prepare the case series according to the AME Case Series (adapted from CARE and PROCESS checklist) and their submission should include a reporting checklist (a reformatted version has been made for the journal) as a supplementary material. The relevant page/line and section/paragraph number in the manuscript should be stated for each item in the checklist. A statement like “We present this case series in accordance with the AME Case Series reporting checklist” should be included at the end of the “Introduction”. The manuscript should also include a Reporting Checklist statement in the footnote (see the “Footnote” section). Failure to do so will result in the manuscript being returned to the authors for their amendment. Please note that the application of a checklist is aimed at transparent and clear reporting to allow a better critical appraisal of the manuscript. The final format of the manuscript should follow the author instruction requirements.

Of note, for case series in surgery, authors are recommended to prepare the manuscript according to the PROCESS Checklist.

The AME Case Series and PROCESS checklists can be downloaded here: AME Case Series, PROCESS.

2.5 Case Report
A case report is an article reporting observations of diseases, clinical findings, or novel/unique treatment outcomes that are relevant to one or several participants/patients in related fields. Only cases of exceptional interest and novelty are considered. Of note, when the number of patients in the article is ≤3, the article will be classified as Case Report. Otherwise, the manuscript will be classified into other categories, e.g., when the number of patients in the article is between 4 and 9, the article will be classified as Case Series; when the number of patients in the article is ≥10 and the article contain statistical analysis, the article will be classified as Original Article (the article format should refer to Original Article).

Word limit: 2,500 words max; 6,000 words max for “Case Report: iMDT Corner”. (excluding references, tables, and figures)
Abstract: 200–350 words max. Structured with:

• Background: state what is known and unknown; why the case report is unique and what it adds to existing literature.
• Case Description: describe the patient’s demographic details and main history, the main diagnosis, interventions, outcomes, and follow-ups.
• Conclusions: summarize the main take-away lesson, clinical impact, and potential implications.

Keywords: 3–5.
Main text: The text should be arranged as Introduction, Case Presentation, Discussion, and Conclusions. In addition, case reports are required to contain a box that highlights the key findings and potential impacts. See the “Main Text” section for details.
References: 35 max.
Figures/Tables: 8 max. (combined)
Contributions: The case report should include a section describing the contribution made by each author to the manuscript. See the “Author Contributions” section for details.
Ethical Statement: Case reports should include an ethical statement indicating whether written consent has been obtained from the subject (or their parent/guardian). See the “Ethical Statement” section for details.
Reporting Checklist: Apart from following the general format as indicated above, authors should prepare the case reports according to the CARE Guidelines (18), and their submission should include a reporting checklist (a reformatted version has been made for the journal) as supplementary material. The relevant page/line and section/paragraph number in the manuscript should be stated for each item in the checklist. A statement like “We present the following case in accordance with the CARE reporting checklist” should be included at the end of the “Introduction”. The manuscript should also include a Reporting Checklist statement in the footnote (see the “Footnote”). Failure to do so will result in the manuscript being returned to the authors for their amendment. Please note that the application of a checklist is aimed at transparent and clear reporting to allow a better critical appraisal of the manuscript. The final format of the manuscript should follow the author instruction requirements.

The reformatted CARE checklist can be downloaded here: CARE.

2.5.1 Case Report: iMDT Corner
A multidisciplinary team approach (MDT) is considered best practice in the treatment planning and care for patients in challenging clinical situations. It is an integrated team approach to health care in which medical and allied healthcare professionals consider all relevant treatment options and collaboratively develop an individual treatment and care plan for each patient.

The “iMDT” with “i’ meaning “international”, is an upgraded version by integrating international perspectives. Different from the traditional MDT which is mainly conducted by physicians within a single hospital, the “iMDT” aims to involve all relevant international health professionals discussing options and making joint decisions about treatment and supportive care plans for the maximum benefit of patients. Embodying the core value “patient comes first”, the “Case Report: iMDT Corner” column is designed as an educational window for healthcare providers.

The column is only open to selected cases with high educational value. For submission to the “Case Report: iMDT Corner”, please write to the editorial office first with your proposal for an evaluation of the educational value.

Apart from following the format of a case report as indicated above, articles submitted for “Case Report: iMDT Corner” should feature a section of the International Multidisciplinary Team (iMDT) discussion. The iMDT Discussion should include two parts of expert opinions: 1. opinions from physicians from the hospital receiving the patient; 2. opinions from the international experts on questions related to the diagnosis and treatment of this patient.

2.6 Surgical Technique
This section is designed to be presented as a detailed "how to" multimedia manual for operative procedures. The manuscript on surgical techniques should include detailed descriptions of the procedures in a step-by-step format. Expert opinions regarding possible pitfalls and the comparison of the described procedure with other methods are encouraged.

Word limit: 5,500 words max. (excluding references, tables, video, and figures)
Abstract: Unstructured, 200–350 words max.
Keywords: 3–5.
Main text: The text should be arranged as Introduction, Preoperative Preparations and Requirements, Step-by-step Description, Postoperative Considerations and Tasks, Tips and Pearls, Discussion and Conclusions. In addition, surgical technique is required to contain a highlight box. See the “Main Text” section for details.
References: No limit.
Figures/Tables: No limit, but 10 figures are deemed sufficient.
Contributions: The surgical technique should include a section describing the contribution made by each author to the manuscript. See the “Author Contributions” section for details.
Videos: Surgical videos are encouraged for this section. We will accept digital files in MP4, Flash video (.flv), MPEG (MPEG video file), mov, avi, and wmv formats or videos on CD/DVD. Check the “Video” section for more details. The corresponding author must confirm in the Copyright Transfer Agreement, that he/she has received a signed release form from each patient recorded on the submitted video. Patients must not be identifiable in these videos. If required, additional video editing by the authors, including the insertion of a voice-over, may also be requested by the editorial office.
Ethical Statement: Surgical technique should include an ethical statement indicating whether written consent has been obtained from the subject (or their parent/guardian). See the “Ethical Statement” section for details.

2.6.1 Reporting Checklist
Apart from following the general format as indicated above, authors should prepare the surgical technique according to the SUPER (Surgical techniqUe rePorting chEcklist and standaRds) guideline and their submission should include a reporting checklist (the reformatted SUPER checklist for the journal can be downloaded here) as a supplementary material. The relevant page/line and section/paragraph number in the manuscript should be stated for each item in the checklist. A statement like “We present this article in accordance with the SUPER reporting checklist” should be included at the end of the “Introduction”. The manuscript should also include a Reporting Checklist statement in the footnote (see the “Footnote” section below). Failure to do so will result in the manuscript being returned to the authors for their amendment. Please note that the application of a checklist is aimed at transparent and clear reporting to allow a better critical appraisal of the manuscript. The final format of the manuscript should follow the author instruction requirements.

2.7 Brief Report
Manuscripts containing pertinent and interesting observations and reports on new observations or studies that do not warrant publication as a full research article will be considered for the Brief Reports. These submissions will undergo full peer review.

Word limit: 2,500 words max. (excluding references, tables, and figures)
Abstract: 200–350 words maximum, unstructured (no use of sub-headers).
Keywords: 3–5.
Main text: unstructured.
References: Up to 35.
Figures/Tables: Up to 8 in total.
Ethical Statement: Brief Reports should include an ethical statement indicating whether written consent has been obtained from the subject (or their parent/guardian). See the “Ethical Statement” section for details.

2.8 Images in Clinical Medicine
Images in Clinical Medicine are classic images of common medical conditions. Images are an important part of much of what we do and learn in medicine. This feature is intended to capture the sense of visual discovery and variety that physicians experience. Images in Clinical Medicine are not intended as a vehicle for case reports. Original, high-quality images are considered for publication (subject to editing and abridgment) provided they do not contain material that has been submitted or published elsewhere.

Word Limit: No limit.
Keywords: Not required.
Abstract: Not required.
References: 10 max.
Figures/Tables: Up to 8 in total.
Ethical Statement: Images in Clinical Medicine should include an ethical statement indicating whether written consent has been obtained from the subject (or their parent/guardian). See the “Ethical Statement” section for details.

2.9 Study Protocol
Study Protocol report planned or ongoing clinical trials, describing the rationale, criteria, and treatment plan(s), and anticipating the results. Since this type of article discusses ongoing or planned trials, manuscripts reporting work that has already been carried out will not be considered, nor will conclusive data regarding outcomes be included.

The format of a Study Protocol may follow a similar format to an Original Article.
Word limit: No limit.
Title: should contain the word “protocol” along with the specific study type (e.g., a randomized controlled trial).
Abstract: 200–350 words structured with the subheadings Background, Methods, Discussion, and Trial Registration.
Keywords: 3–5.
Main text: Study protocols should organize the main text in the Introduction, Methods, and Discussion. Of note, registration details and the study timeline are highly recommended included in the Methods. The Discussion section may consider discussing potential challenges and solutions, strengths and limitations of the protocol, etc.
References: No limit.
Figures/Tables: No limit, but 10 figures are deemed sufficient.
Contributions: Study protocols should include a section describing the contribution made by each author to the manuscript. See the “Author Contributions” section for details.
Ethical Statement: Protocols for studies that require ethical approval, such as clinical trials, are unlikely to be considered without having already received approval. When a study protocol documents any experiment(s) involving human subjects or animals, the authors must indicate an ethical statement both in the methods section and the footnote. See the “Ethical Statement” section for details.

2.9.1 Reporting Checklist
Apart from following the general format as indicated above, authors should prepare the study protocol for interventional trials according to the SPIRIT (Standard Protocol Items: Recommendations for Interventional Trials) Guidelines (20) and their submission should include a reporting checklist (the reformatted SPIRIT checklist for the journal can be downloaded here) as a supplementary material. The relevant page/line and section/paragraph number in the manuscript should be stated for each item in the checklist. A statement like “We present the protocol in accordance with the SPIRIT reporting checklist” should be included at the end of the “Introduction”. The manuscript should also include a Reporting Checklist statement in the footnote (see the “Footnote” section below). Failure to do so will result in the manuscript being returned to the authors for their amendment. Please note that the application of a checklist is aimed at transparent and clear reporting to allow a better critical appraisal of the manuscript. The final format of the manuscript should follow the author instruction requirements.

2.10 Editorial and Editorial Commentary

2.10.1 Editorial
An Editorial is defined as a comment on an article or articles published in the current journal or written in-house by the journal’s editors to discuss a paper, report, policy, event or topic from within the past few months, or in the near future. Editorials are generally solicited by the editorial office and written by recognized leader(s) in the field. 

Word limit: 2,500 words max., excluding references, tables, and figures.
Abstract: Not required.
Keywords: 3–5.
Main text: Unstructured.
References: No limit.
Figures and Tables: 2 max. in total.
Ethical Statement: See the “Ethical Statement” section for details.

2.10.2 Editorial Commentary
The Editors extend an invitation to an expert in the field to discuss a paper, report, event, or topic from within the past few months, or in the near future. The problems addressed by the relevant paper/report/event/topic should be considered within the wider context of the field.

Word limit: 2,500 words max., excluding references, tables, and figures.
Abstract: Not required.
Keywords: 3–5.
Main text: Unstructured.
References: 25 max., including the article being discussed.
Figures and Tables: 2 max. in total.
Ethical Statement: See the “Ethical Statement” section for details.

2.11 Letter to the Editor
We welcome the submission of letters regarding the content of the journal or other topics of interest to our readers. The journal may invite replies from the authors of the original publication, or forward letters to these authors. Correspondence is also referred to as a ‘Letter to the Editor’.

Word limit: 1,000 words max., excluding references, tables, and figures.
Abstract: Not required.
Keywords: Not required.
Main text: Unstructured.
References: 10 max.
Figures and Tables: 1 max.
Ethical Statement: See the “Ethical Statement” section for details.

2.12 Others
In general, CCO does not accept articles that fall outside the above-mentioned categories. If you have any questions regarding the article category for submission to CCO, please contact the Editorial Office at: editor@thecco.net.

3. MANUSCRIPT SUBMISSION REQUIREMENTS

The length of manuscripts must adhere to the specifications under the section “MANUSCRIPT CATEGORIES”.

Manuscripts should be presented in the following order: (i) Title page; (ii) abstract and keywords; (iii) the main text; (iv) Acknowledgments; (v) Footnote; (vi) References; (vii) Tables; (viii) Figures; (ix) Videos; (x) Figure Legends; (xi)Supplementary material.

3.1 Title Page
The title page should include: a) the title of the article; b) the authors’ full names and institutional affiliations; c) the degree information, address [full address for the corresponding author(s)], telephone number and effective e-mail address of the corresponding author(s) (extremely important for subsequent timely communication); d) if available, the 16-digit ORCID of the author(s); e) a running title of no more than 60 characters (including spaces); f) disclaimers (if applicable); g) word count; h) number of figures and tables; i) contributions (required for certain article types; see below detailed description).

3.2 Authorship and Author contributions

3.2.1 Authorship
Authors should meet all four of the ICMJE’s authorship criteria listed below for authorship (1):

1) Substantial contributions to the conception and design of the study; or the acquisition, analysis, or interpretation of the data for the work; AND
2) Drafting the article or reviewing it critically for important intellectual content; AND
3) Final approval of the version to be published; AND
4) Agreement to be accountable for all aspects of the work in ensuring that questions related to the accuracy or integrity of any part of the work are appropriately investigated and resolved.

Contributors who meet fewer than all 4 of the above criteria for authorship should not be listed as authors, but they should be acknowledged. Examples of activities that alone (without other contributions) do not qualify a contributor for authorship are acquisition of funding; general supervision of a research group or general administrative support; writing assistance, technical editing, language editing, and proofreading. Additionally, AI tools cannot be listed as an author of a paper as AI tools cannot meet the requirements for authorship and cannot take responsibility for the submitted work (1-3).

Authors must disclose in the Cover letter, Materials and Methods, and the Acknowledgement for applying any AI tools (e.g., ChatGPT, Bing) in the writing of a manuscript, production of images or graphical elements of the paper, or in the collection and analysis of data. Disclosure should include - but is not limited to - all prompts used to generate new text, or to convert text or text prompts into tables or illustrations; the full prompt used to generate the research results; the time and date of a query; and the AI tool used and its version. Authors are fully responsible for the content of their manuscript, even those parts produced by an AI tool, and are thus liable for any breach of publication ethics. For more recommendations, please refer to the WAME Recommendations on Chatbots and Generative Artificial Intelligence in Relation to Scholarly Publications: https://wame.org/page3.php?id=106 (21).

Please carefully check the authorship of your manuscript before submission. Except for grammatical corrections, any other changes of authorship after submission require a sound scientific justification.

3.2.2 Author contributions
Of note, the “Contributions” section is required for original articles, review articles, clinical practice guidelines, expert consensus, case reports, case series, surgical techniques, and study protocols.

Author contribution describes the contribution each author made to the manuscript. The ‘Contributions’ section should be presented as follows:

(I) Conception and design:
(II) Administrative support:
(III) Provision of study materials or patients:
(IV) Collection and assembly of data:
(V) Data analysis and interpretation:
(VI) Manuscript writing: All authors
(VII) Final approval of manuscript: All authors

Note: With VI and VII, “All authors/Both authors (when there are only two authors)” is obligatory, while the other credits are case-based; The ‘Contributions’ section is not required when there is only one author.

See more details of authorship and contributorship: https://cco.amegroups.org/page/about/authorship-and-contributorship.

3.3 Abstract and Keywords
The abstract must adhere to the specifications under section ‘MANUSCRIPT CATEGORIES’. The abstract should not contain any citations, figures, tables, or undefined abbreviations or acronyms. General statements (e.g., “the significance of the results is discussed’’) should be avoided. After the Abstract, 3-5 keywords should be provided.

Where relevant, the study project registration number (e.g., registration number for a clinical trial, a clinical guideline, a systematic review, and meta-analysis, or an animal study) should be included at the end of the abstract. For studies that have a registration number, this number should be included initially when a trial acronym is used to refer to the trial in the report or to other trials discussed in the paper. For data that have been deposited in a public repository and/or are the subject of analysis elsewhere, the distinctive, persistent data set identifier, the repository name, and the number should be included at the end of the abstract.

3.4 Main Text
The structure of the main text must adhere to the specifications under the section “MANUSCRIPT CATEGORIES”. In general, the main text of many articles in different types contains a) Introduction; b) Methods; c) Results; d) Discussion; and e) Conclusions. However, there are differences and modifications for different types of articles regarding the above sections. Of note, a highlight box is required for some article types.

3.4.1 Highlight Box
A highlight box is used to highly summarize the key findings/recommendations, innovation, and potential implications of the study.

Manuscript categories that require a highlight box: Original Article, Systematic Review, Scoping Review, Clinical Practice Guideline, Expert Consensus, Case Report, Case Series, and Surgical Technique.
Word limit: The box should be concise with no more than 250 words for Original Article, Systematic Review, Scoping Review, Case Report, Case Series, and Surgical Technique or 300 words for Clinical Practice Guideline and Expert Consensus.

Template 1: Highlight Box for Original Article, Systematic Review, Scoping Review, Case Report, and Case Series.

Key findings Report here about the key findings of the study. What is known and what is new? Report here about what is known. Report here about what this manuscript adds. What is the implication, and what should change now? Report here about the implications and actions needed.

Template 2: Highlight Box for Clinical Practice Guideline and Expert Consensus.

Key recommendations Report here about key recommendations. What was recommended and what is new? Report here about what was recommended in existing evidence. Report here about what are the changes of recommendation. What is the implication, and what should change now? Report here about the implications and actions needed.

Template 3: Highlight Box for Surgical Technique

Surgical highlights Report here about highlights of the surgical technique. What is conventional and what is novel/modified? Report here about how conventional surgical techniques are applied. Report here about what modifications or innovations of surgical technique are done. What is the implication, and what should change now? Report here about the implications and actions recommended.

3.4.2 Introduction
The introduction should give a brief description of what we already know and what we don't know, with a clear rationale defense based on the above. The introduction needs to very clearly specify the question the study proposes to answer, and what the purpose of the study is.

For Original Article, Review Article, Systematic Review, Scoping Review, Narrative/Literature Review, Clinical Practice Review, Clinical Practice Guideline, Expert Consensus, Case Report, Case Series, and Study Protocol, we recommend that authors use a structured introduction to increase the readability:

• a) Background
• b) Rationale and knowledge gap
• c) Objective

3.4.3 Methods
Authors should report methods as exhaustively as possible to make the study more transparent and reproducible. Specific reporting guidelines for each article type can be found at: https://www.equator-network.org/ (4)

3.4.4 Results
The report of the study results needs to be properly detailed and paired well with the figures and tables rather than repeating them. It is important to note that the results should be presented objectively and not overly interpreted (interpretation should be done in the Discussion). In particular, the author needs to ensure that the results and data are consistent and accurate throughout the manuscript. Any inconsistencies and inaccuracies in the data and results may cause the editorial office and reviewers to be extra concerned about the scientific validity and authenticity of the study.

Authors can find further requirements and recommendations on statistical considerations of the results in “STATISTICAL REQUIREMENTS”.

3.4.5 Discussion
The discussion should be evidence-based, comprehensive, in-depth, and cutting-edge.

For Original Article, Systematic Review, Scoping Review, Case Report, and Case Series a separate Discussion section is required. And, we recommend that authors use a structured discussion to increase the readability:

• a) Key findings
• b) Strengths and limitations
• c) Comparison with similar research
• d) Explanations of findings
• e) Implications and actions needed

For Review Article, Narrative Review/Literature Review, Clinical Practice Review, Mini-Review, Clinical Practice Guideline, and Expert Consensus, although a separate Discussion section is not required, authors are encouraged to include evidence-based, comprehensive, in-depth, and cutting-edge discussion throughout the main body content. In particular, we recommend including a separate section on strengths and limitations in the main body to promote a more intellectual interpretation.

3.4.6 Conclusions
Conclusions are summaries of the entire article. Conclusions need to be concise, usually using only one paragraph. Conclusions need to be scientifically deducible from the results available and the information presented, not exaggerated, out of scope, or even wrong.

Manuscript categories that require a separate conclusions section: Original Article, Review Article, Systematic Review, Scoping Review, Narrative/Literature Review, Clinical Practice Review, Clinical Practice Guideline, Expert Consensus, Case Report, and Case Series.

3.5 Acknowledgments
All contributors who do not meet the criteria for authorship should be listed in the ‘Acknowledgments’ section. Examples of those who might be acknowledged include an individual who provided purely technical help, writing or language editing assistance, or a department chairperson who provided only general support. If a part of the manuscript has been presented elsewhere (e.g., meeting presentation/poster history), a corresponding statement should be provided in the acknowledgment section. Financial and material support should also be acknowledged.

The ‘Acknowledgments’ section should also detail all funding sources for the work in question. There must be a section “Funding” within the “Acknowledgments” section. If the research was carried out without funding, "None" should be stated in this section.

In providing details of funding, authors should adhere to the following guidance:

• The sentence should begin: ‘This work was supported by …’
• The full official funding agency name should be given, (i.e., ‘National Institute of Health’, not ‘NIH’). Grant numbers should be given in brackets [e.g., (grant number xxxx)].
• Multiple grant numbers should be separated by a comma [e.g. (grant numbers xxxx, yyyy]].
• Agencies should be separated by a semi-colon (with ‘and’ before the last funding agency)
• Where certain sources of funding were received by a specific author, the following text should be added after the relevant agency or grant number: ‘to [author initials]’.

Example: ‘This work was supported by the National Institutes of Health (AA123456 to C.S., BB765432 to M.H.); and the Alcohol & Education Research Council (hfygr667789).’

3.6 Footnote

3.6.1 Reporting Checklist
For articles written in accordance with specific reporting guidelines, the author must include the “Reporting Checklist” section in the footnote and indicate, “The authors have completed the XXXX reporting checklist.”

If the manuscript is accepted for publication, the author’s completed checklist will be published online alongside the manuscript.

3.6.2 Data Sharing Statement
If an original article includes any data that are not publicly available, the authors are required to fill in a data-sharing statement form, which should be submitted along with their manuscript. If the article is accepted for publication, the Data Availability Statement (form) will be published online alongside the article. The data sharing statement form can be downloaded here.

3.6.3 Peer Review File
With a commitment to openness and accountability, and to increase the level of transparency throughout our peer review process, our editorial office has decided to fully implement the transparent peer review (TPR) process for all new submissions from March 15, 2023.

For more details, please refer to: https://cco.amegroups.org/announcement/view/3747.

3.6.4 Conflicts of Interest
All authors will be asked to fill in the ICMJE’s unified disclosure form (the latest version). The form could be downloaded at: https://cdn.amegroups.cn/static/public/coi_disclosure.docx. Each author should submit a separate form and is responsible for the accuracy and completeness of the submitted information. The corresponding author should use the information in the form completed by each author to create the COI statement for the manuscript. The statement (but not the forms) must be included along with the submission. The statement should include the initials of the author along with the conflicts of interest. The following examples show the format in which the Conflicts of Interest statement should appear in the manuscript:

“Conflicts of Interest: All authors have completed the ICMJE uniform disclosure form. The authors have no conflicts of interest to declare.”

“Conflicts of Interest: All authors have completed the ICMJE uniform disclosure form. KSS and VS are former employees of Scanco Medical AG. NV is a current employee of Scanco Medical AG. The other authors have no conflicts of interest to declare.”

If the paper is accepted, the completed ICMJE’s unified disclosure forms will be required and will be published alongside the article.

See the journal’s policy on conflicts of interest: https://cco.amegroups.org/page/about/conflicts-of-interest.

3.6.5 Ethical Statement
Statement #A is a must for every article, followed by statement #B.
Statement #B should be described ①based on whether the specific content of the article requires an additional ethical statement; ②both in the Methods section and the “Ethical Statement” section of Footnote.
Statement #C should be noted as it is related to Informed Consent.

#A. (a Must) Statement for every article

Please note that all articles submitted to our journal must include an Ethical Statement in the Footnote, containing the following wording: “The authors are accountable for all aspects of the work in ensuring that questions related to the accuracy or integrity of any part of the work are appropriately investigated and resolved.”

#B. The specific content of the article requires an additional ethical statement

(a) Human Experiments
For research involving human experiments, the article must include a statement that ethical approval was obtained (or a statement that it was not required and why), including the name of the ethics committee(s) or institutional review board(s), the number/ID of the approval(s), and a statement that the participants gave informed consent before taking part (or a statement that it was not required and why). Authors should also state that the study conformed to the provisions of the Declaration of Helsinki (as revised in 2013), available at: https://www.wma.net/policies-post/wma-declaration-of-helsinki-ethical-principles-for-medical-research-involving-human-subjects (22). For example:

(For prospective experiments) Ethical Statement: The authors are accountable for all aspects of the work in ensuring that questions related to the accuracy or integrity of any part of the work are appropriately investigated and resolved. The study was conducted in accordance with the Declaration of Helsinki (as revised in 2013). The study was approved by the institutional/regional/national ethics/committee/ethics board of ******* (No.: the registration number of the ethics board) and informed consent was obtained from all individual participants.

(For retrospective experiments) Ethical Statement: The authors are accountable for all aspects of the work in ensuring that questions related to the accuracy or integrity of any part of the work are appropriately investigated and resolved. The study was conducted in accordance with the Declaration of Helsinki (as revised in 2013). The study was approved by the institutional/regional/national ethics/committee/ethics board of ******* (No.: the registration number of the ethics board) and individual consent for this retrospective analysis was waived.

(b) Animal Experiments
For any experiments involving animals, the authors must indicate the nature of the ethical review permissions, relevant licenses (e.g., Animal [Scientific Procedures] Act 1986), and national or institutional guidelines for the care and use of animals by which the research was conducted. Describe this information in both the “Method” section and the “Ethical Statement” section in Footnote. For example:

Ethical Statement: The authors are accountable for all aspects of the work in ensuring that questions related to the accuracy or integrity of any part of the work are appropriately investigated and resolved. Experiments were performed under a project license (No.: the license number) granted by the institutional/regional/national ethics/committee/ethics board of *******, in compliance with ******* national or institutional guidelines for the care and use of animals.

In addition, we strongly recommend that authors register experiments that include animals and state the registration number in the methods and footnote. For authors' reference, registration platforms such as Open Science Framework (23) and Animal Study Registry (24) are commonly used.

(c) Case Report and Case Series
Whenever possible, signed consent should be obtained from the patient (or their parent/guardian) to write and publish a Case Report or Case Series. This is particularly important where the unique nature of the incident being reported makes it possible for the subject to be identified (such as when the patient is over 100 years old; the manuscript has photographs or images or has a rare disease). Beyond that, please keep patient details anonymous whenever possible, for example, occupations unrelated to the disease/condition. If informed consent cannot be obtained, for example, if the patient has passed away and the author is unable to obtain signed consent from the guardian or family of the deceased patient, the authors need to state that they have made the best efforts to contact the relative and that the article has been sufficiently anonymized to cause no harm to the patient or his or her family.

Authors should also state that the study conformed to the provisions of the Declaration of Helsinki (as revised in 2013), available at: https://www.wma.net/policies-post/wma-declaration-of-helsinki-ethical-principles-for-medical-research-involving-human-subjects (22). Please describe this information in both the “Case Presentation” section and the “Ethical Statement” section on Footnote. For example:

(For manuscripts that have patient consent) Ethical Statement: The authors are accountable for all aspects of the work in ensuring that questions related to the accuracy or integrity of any part of the work are appropriately investigated and resolved. All procedures performed in this study were in accordance with the ethical standards of the institutional and/or national research committee(s) and with the Helsinki Declaration (as revised in 2013). Written informed consent was obtained from the patient for the publication of this case report and accompanying images. A copy of the written consent is available for review by the editorial office of this journal.

(For manuscripts that do not have patient consent) Ethical Statement: The authors are accountable for all aspects of the work in ensuring that questions related to the accuracy or integrity of any part of the work are appropriately investigated and resolved. All procedures performed in this study were in accordance with the ethical standards of the institutional and/or national research committee(s) and with the Helsinki Declaration (as revised in 2013). Written informed consent for publication of this case report and accompanying images was not obtained from the patient or the relatives after all possible attempts were made.

(For manuscripts that are waived from patient consent) Ethical Statement: The authors are accountable for all aspects of the work in ensuring that questions related to the accuracy or integrity of any part of the work are appropriately investigated and resolved. All procedures performed in this study were in accordance with the ethical standards of the institutional and/or national research committee(s) and with the Helsinki Declaration (as revised in 2013). Publication of this case report and accompanying images was waived from patient consent according to the xxx ethics committee/institutional review board.

#C. Informed Consent
Written informed consent for the publication of details relating to a person must be obtained from that person (or their parent or legal guardian in the case of children under 18) for all manuscripts that include images, details, or videos. The consent must be for publication of their details under the Creative Commons Attribution-NonCommercial-NoDerivatives 4.0 International License (CC BY-NC-ND 4.0) (such that they will be freely available on the internet). If the person has deceased, consent for publication must be acquired from their next of kin. A statement that written informed consent for publication was obtained must be included in the manuscript.

To get consent for publication, authors can use the consent form (download the form for the patient or the form for the participant) or a consent form from their institution or region, if suitable. The consent form must specify that the details/images/videos will be freely available on the internet and that the general public will be able to view them. Authors do not need to provide a copy of the consent form to the editorial office; however, if the Editor requests it, the consent form must be provided and will be kept confidential.

Consent for image publication may not be necessary for circumstances where photographs are completely unidentified and there are no details on persons mentioned within the text. The Editor has the final say on whether or not consent to publish is required.

The Editorial Office may request copies of the informed consent documentation at any time. While the Editorial Board recognizes that it might not always be possible or appropriate to seek such consent, the onus will be on the authors to demonstrate that this exception applies in their case.

The Journal retains the right to reject any manuscript based on unethical conduct in either human or animal studies.

3.7 References
Sources should be referenced according to the Vancouver reference style. Referencing AI-generated material as the primary source is not acceptable. For guidance on references, please refer to: https://www.icmje.org/recommendations/.

In the text, references should be identified using numbers in round brackets. Where more than one number is required, they should appear consecutively [e.g., "cancer-related mortality (19)”; “adenocarcinoma (29,30)”; “raised significantly (15, 20, 31-33)”]. References (including in the text, tables, and figure legends) should be numbered consecutively and consistently according to the order in which they first appear in the text.

In the reference list, the titles of journals should be abbreviated according to the style used in Index Medicus. For reports with up to three authors, all the author names should be listed. However, if a report has more than three authors, the first three authors should be listed followed by “et al.”

• McLeer-Florin A, Lantuéjoul S. Why technical aspects rather than biology explain cellular heterogeneity in ALK-positive nonsmall cell lung cancer. J Thorac Dis 2012;4:240-1.
• Lin X, Li W, Lai J, et al. Five-year update on the mouse model of orthotopic lung transplantation: Scientific uses, tricks of the trade, and tips for success. J Thorac Dis 2012;4:247-58.

Below are two examples for the management of the reference:
a. If you manage references manually or in another way, you could refer to the reference example below:
Lin X, Li W, Lai J, et al. Five-year update on the mouse model of orthotopic lung transplantation: Scientific uses, tricks of the trade, and tips for success. J Thorac Dis 2012;4:247-58.
b. If you use “Endnote” (a commercial reference management software package produced by Clarivate Analytics, used to manage bibliographies and references when writing essays and articles), the reference style file for AME journals can be directly downloaded here: https://cdn.amegroups.cn/static/public/reference-style.ens.

3.8 Tables
Tables are recommended to be provided in separate files. Tables should be self-contained and complement, but not duplicate, the information contained in the text. All tables should be numbered consecutively in the order in which they are mentioned in the text. Each table should be on a separate page; tables must be typed and editable in a tabular format that is convenient for copyediting and typesetting; they should not be inserted as images. Please refer to the examples for different cases.

Each column must have an appropriate heading and, if measurements are given, the units should be provided in the column heading. Column headings should be brief, with units of measurement in parentheses; all abbreviations must be defined in footnotes. Footnote symbols: †, ‡, §, ¶, should be used (in this order), and *, **, *** should be reserved for P values. Statistical measures such as SD or SEM should be identified in the headings.

If the tables have been reproduced from another source, a letter or permission from the copyright holder (usually the publisher) authorizing the reproduction of the material must be submitted as supplemental material along with the manuscript.

3.9 Figures
Figures should be provided in separate files. All illustrations (line drawings and photographs) are classified as figures. Figures should be cited in the order in which they appear in the text. Magnifications should be indicated using a scale bar on the illustration.

• File types, resolution, size: Please refer to the specification (file types, resolution, image size, file size, etc.) for more detailed requirements. For the flow diagram of a study/trial (e.g. CONSORT diagram), please provide the diagram in an editable form, e.g. Word (.doc) or PowerPoint (.ppt) file, etc.
  For photographs, clinical images, photomicrographs, gel electrophoresis, and other types that include labels, arrows, or other markers, please submit 2 versions: one version with the markers and one without. An explanation for all labels, arrows, or other markers should be included in the figure legend.
• Figure legends: Legends should be provided for figures, including the figure title, the full name of any abbreviation in the figure, a detailed description of any symbol in the figure (e.g., some color notation or arrows), and a separate description of each figure if it is a combination of several figures, etc.
• Copyright: If the figures have been reproduced from another source, a letter from the copyright holder (usually the publisher) authorizing the reproduction of the material must be attached to the cover letter (see the “COPYRIGHT AND PERMISSION” section).
• Patient Privacy: Where illustrations include recognizable individuals, living or deceased, great care must be taken to ensure that consent for publication has been given (see the “Ethical Statement” section). A statement like “This image is published with the patient/participant’s consent.” should be included at the end of the figure legend. Patient anonymity should be preserved. Nonessential identifying details should be omitted. For example, photographs need to be cropped sufficiently to prevent human subjects from being recognized and the eyes and eyebrows (at a minimum) must be masked using Coarse Pixilation to make the individual unrecognizable. However, masking the eye region in photographs of patients is inadequate protection of anonymity. If identifying characteristics are de-identified, authors should ensure that such changes do not distort scientific meaning.

In-text citations

• Cite figures with the format: Figure 1A, Figure 1B, Figure 2, Figure 3, etc. When consecutive subparts of a figure are cited, they should be cited as Figure 1A-1D, Figure 2B-2L, etc.
• Cite figures in ascending numeric order upon the first appearance in the manuscript file. This includes citations to text boxes and tables. In the published article, figures are inserted according to the placement of their first citation and caption in the article.
• Lettered subparts of whole figures may be cited in any order in the text if the first mention of each whole figure is in numerical order. For example, Figure 1 contains 4 subparts (i.e., Figure 1A, 1B, 1C, 1D). These subparts should be cited consecutively unless Figure 1 as a whole is already cited before Figure 1A, 1B, 1C, and 1D.

3.9.1 Western Blot Figures
A separate note is worthwhile, as the problem of Western Blot figures is particularly serious in published studies in the academic community. To further improve the reporting transparency of Western Blot figures when Western Blot experiments are used in a study, we strongly recommend that its report adopt several recommendations as follows.

• Ensure that the raw data is accessible to readers. The authors could provide the original images without cropping or any other processing in the Supplement.
• Make sure that the Western Blot figure contains at least one molecular weight marker above and below the protein of interest.
• Crop as few as possible. The presence of non-specific bands is very common and the reader needs to be aware of these.
• Better to present with dot plots, which can inform readers about sample size and spread of data.
• Report Methods in detail, including the amount of total protein loaded onto the gel, details of the membrane blocking protocol, antibody identifiers and details of antibody labeling protocol, type and number of replicates performed, etc.

For more details, examples, and templates on how to better report Western Blot figures authors can view: https://osf.io/yr7am (25); https://pubmed.ncbi.nlm.nih.gov/36095010/ (26)

3.10 Videos
Videos should be provided in separate files. The journal will accept digital files in mp4, flash video (flv.), MPEG (MPEG video file), DVD video, mov., avi., and mwv. formats or videos on CD / DVD. Contributors are asked to be succinct, and the editorial office reserves the right to request a shorter video if necessary. Video files can be submitted online at: https://cco.amegroups.org/pages/view/submit-multimedia-files.

• Duration: Video files should be limited to 20 minutes.
• Quality: Please set the video aspect ratio as 4:3 or 16:9 (widescreen). The original video should be of high quality with the resolution ≥1280×720, the frame rate ≥24 frames per second, and the bit rate ≥5 Mbps.
• In-video text and audio: Videos should have text or symbols or audio descriptions. All text notes, explanations, descriptions, etc. in the video must be provided in English. Any patient information should be erased from the video.
• Video legends: Legends should be provided for the video files. The video files should be numbered consecutively in their order of reference in the text.
• Copyright: If the videos have been reproduced from another source, a letter from the copyright holder (usually the publisher) authorizing the reproduction of the material must be attached to the cover letter. It is especially worth noting that if background music appears in a video, the author should also obtain authorization from the copyright owner of that music if that music is involved in copyright licensing (see the “COPYRIGHT AND PERMISSION” section).
• File name: please name the videos as Video 1, Video 2, Video S1, Video S2, etc. upon submission.

In-text citations

• Cite videos with the format: Video 1, Video 2, Video S1, Video S2, etc.
• Cite videos in ascending numeric order upon the first appearance in the manuscript file.

For promotion, all accepted videos will be subsequently included in AME Surgical Video Database (ASVIDE: https://www.asvide.com) and its youtube channel (https://www.youtube.com/channel/UCA4NnVYmMW2NS5QrnLEVQNg).

3.11 Supplementary Appendix
The Supplementary Appendix should be paginated, with a table of contents, followed by the list of investigators (if there are any), text (such as methods), figures, tables, and then references. The supplementary appendix should not be included in the article’s reference list.

The Appendix must be submitted in a Word file. The Appendix will not be edited for style. It will be presented online as additional information provided by the authors.

The published article will contain a statement that supplementary material exists online and will provide the reader with a URL and/or link. Refer to the following example for how to reference the supplementary appendix in the text of the article: “Many more regressions were run than can be included in the article. The interested reader can find them in a supplementary appendix online.”

4. STATISTICAL REQUIREMENTS

Regardless of the article type, the presentation of data in your article should follow the SAMPL guidelines for statistics, as shown in detail, linked to: https://www.equator-network.org/wp-content/uploads/2013/03/SAMPL-Guidelines-3-13-13.pdf (27).

Of note:

• The authors should describe the statistical methods in as much detail as possible so that readers with the requisite knowledge and access to the data can verify the results reported in the article.
• If possible, quantify the results and provide the quantified results and associated parameters of measured uncertainty as appropriate (e.g., confidence intervals) and avoid providing only the results of statistical hypothesis tests (e.g., P values) because they do not convey important information about statistical effects. For example, reporting "2.75; 95% CI: −1.89 to 3.86; P=0.26".
• When 95% CIs are wide, statistics should be interpreted with caution, whether or not they are statistically significant.
• Unless the study design calls for the use of a one-sided test, such as a noninferiority trial, other reported P values should be two-sided tests.
• For secondary, subgroup analyses, the possibility of Type I errors due to multiple comparisons should be described and the interpretation of such analyses should be done with caution, similarly for post hoc analyses.
• Caution should be taken for the cases of P=0 and P=1.

Reporting of P values:

• The description of the P value should be in the uppercase format, i.e., "P".
• If P value <0.001, report "P<0.001" to avoid reporting unnecessarily excessive precision (except hypothesis tests that include correlations or studies with exponentially small P values, such as genetic association studies, which can be reported exponentially, e.g., P=1×10^-5).
• If 0.001≤ P value <0.01, report the specific P value to 3 decimal places, e.g., "P=0.001" or "P=0.009".
• If P value≥0.01, report the specific P value to 2 decimal places, e.g., "P=0.01" "P=0.06" "P=0.10" "P=0.90". When the P value is near 0.05, report the specific P value to 3 decimal places, e.g., "P=0.046" or "P=0.052".
• If the P value is >0.99, report "P>0.99".
• Do not report "not significant" simply because the data is greater than an arbitrary value, and do not report only vague bounds such as P<0.05, as described above, but report the exact P value.

5. STYLE OF THE MANUSCRIPT

5.1 Vancouver Style
Manuscripts must follow the style of the Vancouver agreement detailed in the International Committee of Medical Journal Editors’ revised ‘Uniform Requirements for Manuscripts Submitted to Biomedical Journals: Writing and Editing for Biomedical Publication’, as presented at: http://www.ICMJE.org/ (1).

• Author name: Each author’s given name should be followed by their surname. The first letter of the surname should be capitalized. A hyphen can be used in the surname depending on the rule in the author’s region.
  Note: Author names will be published exactly as they appear in the manuscript file. Please double-check the information carefully to make sure it is correct. If applicable, an ORCID should be placed after the name of the author.
• Abbreviation of an author’s name: The first letter of each capitalized word will be used for the name’s abbreviation, i.e., “Shaoling Li” becomes “SL.” The first letter of the second name SHOULD NOT be capitalized, or else it will be included in the abbreviation. However, if the author wishes to use an abbreviation that includes their second name, they should write their second name using a hyphen to connect it with its anterior word, i.e., “Shao-Ling Li” to become “SLL.”
• Spelling: British or American spelling is acceptable but must be consistent throughout.
• Numbers: for numbers below 10, use the full English spelling, e.g., "nine" instead of "9"; for numbers ≥10, use the Arabic numerals; for numbers ≥1,000, use the thousand separator, i.e., "1,000" instead of "1000".
• Italics: Medical Latin words and gene names need to be italicized, e.g., in vivo, in vitro.
• Units: All measurements must be given in SI or SI-derived units. For more information about SI units, please go to the Bureau International des Poids et Mesures (BIPM) website at: https://www.bipm.org/en/about-us (28).
• Abbreviations: must be used sparingly and only where they ease the reader’s task by reducing the repetition of long, technical terms. Initially, the full term should be given, followed by the abbreviation in parentheses. Thereafter, only the abbreviation should appear.
• Trade names: Drugs should be referred to by their generic names. If proprietary drugs have been used in the study, these should be referred to by their generic name, with the proprietary name and the name and location of the manufacturer mentioned in parentheses.
• Format: Text should be double-spaced throughout. The pages should be numbered.
• Font: A readable font (e.g., Arial, Calibri, Times New Roman, or Verdana) with 10 or 12 pt. font size.

5.2 Language
CCO only publishes articles written in English. British or American spelling is acceptable but must be consistent throughout. We recommend language polish for non-native speaker authors. We recognize AME Editing Service and other platforms for language polishing.

5.3 Data Citation
We are committed to improving the openness, transparency, and reproducibility of research, and believe research data citation through standard reference lists offers an easy way to access data for reproducible research.

To support best practices in data citation, AME has endorsed the FORCE11 Data Citation Principles (https://www.force11.org/datacitationprinciples) (29). According to the FORCE11 Data Citation Principles, data can be cited in the same way as article, book, and web citations, and authors are required to include data citations as part of their reference list.

Data citation is applicable for data held within institutional, subject-focused, or more general data repositories. When citing or making claims based on data, authors should refer to the data at the relevant place in the main text of the manuscript and include a formal citation in the reference list. We recommend the format proposed in the Joint Declaration of Data Citation Principles (29).

Below is an example of an in-text data citation:

[dataset] Authors; Year; Dataset title; Data repository or archive; Version (if any); Persistent identifier (e.g., DOI)

“[dataset]” should be included immediately before the reference so it can be properly identified as a data reference.

5.4 Equations
Equations should be numbered sequentially with Arabic numerals; these should appear right in parentheses. All variables should appear in italics. Use the simplest possible form for all mathematical symbols. For example:

• “a2+b2=c2” equations: normal text format.
• All other equations: a graphic of the entire equation should be produced using MathType and inserted into the main body of the text as an object.

5.5 Abbreviations and Symbols
Use as few abbreviations as possible, as too many abbreviations increase readers' reading load, slow down reading, and make comprehension more difficult. When abbreviations are considered, use only standard abbreviations. All abbreviations should be defined when they are first used in the text unless the abbreviation is a standard unit of measurement and a list of full terms should be provided in the manuscript.

6. COPYRIGHT AND PERMISSIONS

For specifications, please refer to: https://cco.amegroups.org/page/about/copyright-and-permission

7. PEER REVIEW PROCESS

For specifications, please refer to: https://cco.amegroups.org/pages/view/peer-review-process

8. ARTICLE PROCESSING CHARGES

For specifications, please refer to: https://cco.amegroups.org/pages/view/article-processing-charges

9. PROOFS
Page proofs will be sent to the author via e-mail. Page proofs should be returned within three working days, preferably by e-mail. Corrections should be marked on the actual proof and provided in a numbered list. Lengthy additions should be avoided but, when necessary, should be provided in an MS Word file with explicit instructions regarding placement.

10. OFFPRINTS AND REPRINTS
Authors will be sent a free URL link to the published online article for their personal use. Authors who wish to purchase hard-copy offprints should fill in the offprint order form, which will be sent with the author’s proof. Orders should be sent to the Editorial Office. Orders for reprints should be sent to the Publisher’s Office.

11. SUBMITTING AND TRACKING MANUSCRIPTS
All articles are submitted and the entire review process is managed electronically through the OJS system (https://cco.amegroups.org/login), which has been developed to provide authors with a straightforward online submission process.

For any questions, please contact our Editorial Office by e-mail: editor@thecco.net.

References*
1. https://www.icmje.org/recommendations/
2. https://publicationethics.org/
3. https://wame.org/policies
4. https://www.equator-network.org/
5. https://www.equator-network.org/reporting-guidelines/consort/
6. https://www.cdc.gov/trendstatement/
7. https://www.strobe-statement.org/
8. https://www.equator-network.org/reporting-guidelines/stard/
9. http://www.prisma-statement.org/?AspxAutoDetectCookieSupport=1
10. https://www.nc3rs.org.uk/our-portfolio/arrive-animal-research-reporting-vivo-experiments
11. https://www.equator-network.org/reporting-guidelines/tripod-statement/
12. https://www.equator-network.org/reporting-guidelines/sager-guidelines/
13. https://scicrunch.org/resources
14. https://www.cochranelibrary.com/about/about-cochrane-reviews
15. https://www.equator-network.org/reporting-guidelines/prisma-scr/
16. http://www.guidelines-registry.org
17. http://www.right-statement.org/
18. https://www.care-statement.org/
19. http://www.thesuper.org/
20. https://www.equator-network.org/reporting-guidelines/spirit-2013-statement-defining-standard-protocol-items-for-clinical-trials/
21. https://wame.org/page3.php?id=106
22. https://www.wma.net/policies-post/wma-declaration-of-helsinki-ethical-principles-for-medical-research-involving-human-subjects/
23. https://osf.io/
24. https://www.animalstudyregistry.org/asr_web/index.action
25. https://osf.io/yr7am
26. https://pubmed.ncbi.nlm.nih.gov/36095010/
27. https://www.equator-network.org/wp-content/uploads/2013/03/SAMPL-Guidelines-3-13-13.pdf
28. https://www.bipm.org/en/about-us
29. https://force11.org/info/joint-declaration-of-data-citation-principles-final/

*Please note for better guidance and illustration, external links are included in the references but the journal does not endorse or take responsibility or liability for any content, advertising, products, or other materials on the externally linked sites, and does not take responsibility for the sites' availability.