A comparative meta-analysis of Rorschach and MMPI validity

Two previous meta-analyses concluded that average validity coefficients for the Rorschach and the MMPI have similar magnitudes (L. Atkinson, 1986; K. C. PI. Parker, R. K. Hanson, & J. Hunsley, 1988), but methodological proble ms in both meta-analyses may have impeded acceptance of these results (H. N . Garb, C. M. Florio, & W. M. Grove, 1998). We conducted a new meta-analysi s comparing criterion-related validity evidence for the Rorschach and the M MPI. The unweighted mean validity coefficients (fs) were .30 for MMPI and . 29 for Rorschach, and they were not reliably different (p = .76 under fixed -effects model, p = .89 under random-effects model). The MMPI had larger va lidity coefficients than the Rorschach for studies using psychiatric diagno ses and self-report measures as criterion variables, whereas the Rorschach had larger validity coefficients than the MMPI for studies using objective criterion variables.