| Item | Recommendation | Page | |
| Title and abstract | 1 | (a) Indicate the study’s design with a commonly used term in the title or the abstract | 1 |
| (b) Provide in the abstract an informative and balanced summary of what was done and what was found | 1 | ||
| Introduction | |||
| Background/rationale | 2 | Explain the scientific background and rationale for the investigation being reported | 2 |
| Objectives | 3 | State specific objectives, including any prespecified hypotheses | 2–3 |
| Methods | |||
| Study design | 4 | Present key elements of study design early in the paper | 3 |
| Setting | 5 | Describe the setting, locations, and relevant dates, including periods of recruitment, exposure, follow-up, and data collection | 3 |
| Participants | 6 | (a) Give the eligibility criteria, and the sources and methods of selection of participants | 3 |
| Variables | 7 | Clearly define all outcomes, exposures, predictors, potential confounders, and effect modifiers. Give diagnostic criteria, if applicable | 3 |
| Data sources/measurement | 8 * | For each variable of interest, give sources of data and details of methods of assessment (measurement). Describe comparability of assessment methods if there is more than one group | 3 |
| Bias | 9 | Describe any efforts to address potential sources of bias | 13 |
| Study size | 10 | Explain how the study size was arrived at | 3 |
| Quantitative variables | 11 | Explain how quantitative variables were handled in the analyses. If applicable, describe which groupings were chosen and why | 3–4 |
| Statistical methods | 12 | (a) Describe all statistical methods, including those used to control for confounding | 3–4 |
| (b) Describe any methods used to examine subgroups and interactions | 4 | ||
| (c) Explain how missing data were addressed | N/A * | ||
| (d) If applicable, describe analytical methods taking account of sampling strategy | N/A * | ||
| (e) Describe any sensitivity analyses | N/A * | ||
| Results | |||
| Participants | 13 * | (a) Report numbers of individuals at each stage of study—e.g., numbers potentially eligible, examined for eligibility, confirmed eligible, included in the study, completing follow-up, and analysed | 3 |
| (b) Give reasons for non-participation at each stage | 3 | ||
| (c) Consider use of a flow diagram | 3 | ||
| Descriptive data | 14 * | (a) Give characteristics of study participants (e.g., demographic, clinical, social) and information on exposures and potential confounders | 4–7 |
| (b) Indicate number of participants with missing data for each variable of interest | 7 | ||
| Outcome data | 15 * | Report numbers of outcome events or summary measures | 7–11 |
| Main results | 16 | (a) Give unadjusted estimates and, if applicable, confounder-adjusted estimates and their precision (e.g., 95% confidence interval). Make clear which confounders were adjusted for and why they were included | 4 |
| (b) Report category boundaries when continuous variables were categorized | 4 | ||
| (c) If relevant, consider translating estimates of relative risk into absolute risk for a meaningful time period | N/A * | ||
| Other analyses | 17 | Report other analyses done—e.g., analyses of subgroups and interactions, and sensitivity analyses | N/A * |
| Discussion | |||
| Key results | 18 | Summarise key results with reference to study objectives | 11 |
| Limitations | 19 | Discuss limitations of the study, taking into account sources of potential bias or imprecision. Discuss both direction and magnitude of any potential bias | 13 |
| Interpretation | 20 | Give a cautious overall interpretation of results considering objectives, limitations, multiplicity of analyses, results from similar studies, and other relevant evidence | 11–13 |
| Generalisability | 21 | Discuss the generalisability (external validity) of the study results | 11–13 |
| Other information | |||
| Funding | 22 | Give the source of funding and the role of the funders for the present study and, if applicable, for the original study on which the present article is based | 13 |
| * N/A: Not applicable. | |||