Table 3 TRIPOD checklist was followed for the development and the validation of the prognostic model

Title

1

Identify the study as developing and/or validating a multivariable prediction model, the target population, and the outcome to be predicted.

1

Abstract

2

Provide a summary of objectives, study design, setting, participants, sample size, predictors, outcome, statistical analysis, results, and conclusions.

2–3

Background and objectives

3a

Explain the medical context (including whether diagnostic or prognostic) and rationale for developing or validating the multivariable prediction model, including references to existing models.

3–4

3b

Specify the objectives, including whether the study describes the development or validation of the model or both.

4–5

Source of data

4a

Describe the study design or source of data (e.g. randomized trial, cohort, or registry data), separately for the development and validation data sets, if applicable.

5

4b

Specify the key study dates, including start of accrual, end of accrual, and, if applicable, end of follow-up.

5

Participants

5a

Specify key elements of the study setting (e.g. primary care, secondary care, general population) including number and location of centres.

5–6

5b

Describe eligibility criteria for participants.

5–6

5c

Give details of treatments received, if relevant.

5–6

Outcome

6a

Clearly define the outcome that is predicted by the prediction model, including how and when assessed.

4,6

6b

Report any actions to blind assessment of the outcome to be predicted.

Not relevant

Predictors

7a

Clearly define all predictors used in developing or validating the multivariable prediction model, including how and when they were measured.

7, 13, 16, Fig. 1

7b

Report any actions to blind assessment of predictors for the outcome and other predictors.

Not relevant

Sample size

8

Explain how the study size was arrived at.

8, 14

Missing data

9

Describe how missing data were handled (e.g. complete-case analysis, single imputation, multiple imputation) with details of any imputation method.

9–10

Statistical analysis methods

10a

Describe how predictors were handled in the analyses.

7–10

10b

Specify type of model, all model-building procedures (including any predictor selection), and method for internal validation.

7–10

10d

Specify all measures used to assess model performance and, if relevant, to compare multiple models.

10–12

Risk groups

11

Provide details on how risk groups were created, if done.

Not relevant

Participants

13a

Describe the flow of participants through the study, including the number of participants with and without the outcome and, if applicable, a summary of the follow-up time. A diagram may be helpful.

Table 1 and Appendix Table 4

13b

Describe the characteristics of the participants (basic demographics, clinical features, available predictors), including the number of participants with missing data for predictors and outcome.

Table 1 and Appendix Table 4

Model development

14a

Specify the number of participants and outcome events in each analysis.

Table 1 and Appendix Table 4

14b

If done, report the unadjusted association between each candidate predictor and outcome.

Not relevant

Model specification

15a

Present the full prediction model to allow predictions for individuals (i.e., all regression coefficients, and model intercept or baseline survival at a given time point).

Table 2

15b

Explain how to use the prediction model.

13, 15

Model performance

16

Report performance measures (with CIs) for the prediction model.

13, Table 2

Limitations

18

Discuss any limitations of the study (such as nonrepresentative sample, few events per predictor, missing data).

16–17

Interpretation

19b

Give an overall interpretation of the results, considering objectives, limitations, and results from similar studies, and other relevant evidence.

15–17

Implications

20

Discuss the potential clinical use of the model and implications for future research.

15–17

Supplementary information

21

Provide information about the availability of supplementary resources, such as study protocol, Web calculator, and data sets.

12, 13, 15

Funding

22

Give the source of funding and the role of the funders for the present study.

29