Reassessing the "traditional background hypothesis" for elevated MMPI and MMPI-2 Lie-scale scores

Area of Science:

• Psychological assessment
• Personality psychology
• Psychometrics

Background:

• The Minnesota Multiphasic Personality Inventory (MMPI) Lie (L) scale measures conscious efforts to deny flaws and appear overly positive.
• The MMPI-2 manual suggests traditional and religious backgrounds may explain elevated L scale scores (65T-79T).

Purpose of the Study:

• To evaluate the hypothesis that religious backgrounds lead to elevated MMPI L scale scores.
• To determine if religious individuals exhibit "fake good" impression management or virtuousness.

Main Methods:

• Reviewed 11 studies using the original MMPI with religious samples.
• Conducted a meta-analysis of 12 MMPI-2 studies comparing L scores of religious samples to normative data.

Main Results:

• Only one of the 11 original MMPI studies found an elevated mean L score.
• Meta-analysis showed significant heterogeneity (I2 = 87.1).
• Religious samples had slightly higher L scores (d¯ = 0.54), averaging 5 t-score points higher, but not reaching manual-specified limits.

Conclusions:

• Religious group membership minimally impacts MMPI-2 L scale scores, accounting for approximately 5 t-score points.
• The interpretation of these modest elevations as "fake good" or religious virtuousness remains inconclusive.