Are separate black and white MMPI norms needed? An IQ-controlled comparison of accused murderers

Investigated racial differences in MMPI responding by comparing samples of black and white males charged with murder (N = 160). Mancova was used to control statistically for the effects of intelligence on racial differences. Prior to the use of Mancova blacks had significantly higher scores on F and MA. When the effects of intelligence were controlled F and MA were no longer significantly different for blacks and whites. However, with black and white SS equated on IQ, significant differences emerged on the K and SI scales. These results indicate that construction of separate black and white norms for violent offenders is premature. More research is needed on variables that affect individual differences on the MMPI.