On the feasibility of criterion-related validity: The effects of range restriction assumptions on needed sample size

Abstract

F. L. Schmidt et al (see record 1976-29035-001 ) argued that the average (median sample size 68) validity study has a 50% chance of detecting validity if validity exists. They assumed direct range restriction (RR) in determining the sample size needed for adequate power. Because indirect RR is more typical, 4 tables indicating required sample sizes under indirect RR are presented. Contrary to Schmidt et al, sample sizes needed under indirect RR are substantially smaller than those needed under direct RR. Under indirect RR, the average validity study has a 75% chance of detecting validity if validity exists when a 1-tailed test can be used. (13 ref) (PsycInfo Database Record (c) 2025 APA, all rights reserved)