There is no such thing as a validated prediction model

BMC Medicine, vol. 21, pp. 70

Abstract

BACKGROUND: Clinical prediction models should be validated before implementation in clinical practice. But is favorable performance at internal validation or one external validation sufficient to claim that a prediction model works well in the intended clinical context? MAIN BODY: We argue to the contrary because (1) patient populations vary, (2) measurement procedures vary, and (3) populations and measurements change over time. Hence, we have to expect heterogeneity in model performance between locations and settings, and across time. It follows that prediction models are never truly validated. This does not imply that validation is not important. Rather, the current focus on developing new models should shift to a focus on more extensive, well-conducted, and well-reported validation studies of promising models. CONCLUSION: Principled validation strategies are needed to understand and quantify heterogeneity, monitor performance over time, and update prediction models when appropriate. Such strategies will help to ensure that prediction models stay up-to-date and safe to support clinical decision-making.

Authors 4

1. Ben Van Calster Aachen Department of Biomedical Data Sciences

   Leiden University Medical Center · KU Leuven

   Affiliation as printed

   Department of Biomedical Data Sciences, Leiden University Medical Center, Leiden, Netherlands

   Department of Development and Regeneration, KU Leuven, Leuven, Belgium

   EPI-Center, KU Leuven, Leuven, Belgium

2. Ewout Willem Steyerberg

   KU Leuven

   Affiliation as printed

   Department of Development and Regeneration, KU Leuven, Leuven, Belgium

3. Laure Wynants

   Maastricht University · Care and Public Health Research Institute · KU Leuven

   Affiliation as printed

   Department of Development and Regeneration, KU Leuven, Leuven, Belgium

   Department of Epidemiology, CAPHRI Care and Public Health Research Institute, Maastricht University, Maastricht, Netherlands

   EPI-Center, KU Leuven, Leuven, Belgium

4. Maarten van Smeden corresponding

   Utrecht University · University Medical Center Utrecht

   Affiliation as printed

   Julius Center for Health Sciences and Primary Care, University Medical Center Utrecht, Utrecht University, Universiteitsweg 100, 3584 CG, Utrecht, Netherlands. M.vanSmeden@umcutrecht.nl

   Julius Center for Health Sciences and Primary Care, University Medical Center Utrecht, Utrecht University, Universiteitsweg 100, 3584 CG, Utrecht, Netherlands