Need to evaluate regression to the mean.
Shephard
Roy J
RJ
D000072038:Cardiac Rehabilitation; D004812:Epidemiologic Methods; D005081:Exercise Therapy / Q000379:methods*; D006334:Heart Function Tests; D006801:Humans; D016032:Randomized Controlled Trials as Topic; D012044:Regression Analysis; D012680:Sensitivity and Specificity