Table 2 Quantitative prediction error analysis to quantify the impact of anticipated predictor measurement heterogeneity at implementation of a prognostic model in clinical practice (details in section “Quantifying the impact of anticipated predictor measurement heterogeneity between validation and implementation setting” of the main text)

1. State the prediction target.

2. Report whether predictor measurement procedures in the validation setting correspond to those at implementation.

3. Identify one predictor that is expected to be measured using a different procedure in the implementation setting than in the validation setting.

4. Define a model for the relation between the measurement in the validation study and its equivalent in the implementation setting.

5. Perform a literature search to establish a range for the size of the possible parameters of predictor measurement heterogeneity.

6. Simulate the scenarios of anticipated measurement heterogeneity to assess the possible impact on predictive performance.

7. Report the impact of anticipated predictor measurement heterogeneity on predictive performance at implementation in clinical practice.