“Training Effect” in the Design of a Longitudinal Study

Abstract

An attempt was made to detect possible effects of familiarization (“training effect”) in the interpretation of data collected repeatedly on children. During a longitudinal study on child growth we looked for such effects on different performance tests done at various ages. We noticed that work capacity tests (PWC₁₇₀; V̇_O2 max) were occasionally subjected to interferences from familiarization. We conclude that a proper interpretation of repeated measurements must take into account possible biases originating from “training effect.”