The study utilized the measurement meta-analytic method called "reliability generalization" to examine (a) the typical reliability, (b) the variability of score reliability, and (c) the factors predicting variability of score reliability on the three MMPI validity scales. Across studies the reliability coefficients on the three validity scales ranged from .16 to .93, with the F scale having the most variability, as might be expected. Regression analyses suggested that the age of participant best predicted the variation of reliability coefficients.