Identifying positive impression management using the MMPI-2 and the MMPI-2-RF: A meta-analysis.

Objective: Individuals may be motivated to conceal or minimize psychological symptoms and engage in positive impression management (PIM) in order to achieve desired outcomes across high stakes contexts (e.g. fitness for duty evaluations, pre-sentencing assessments, medical procedure evaluations, civil commitment). Despite the importance of this topic, the most recent meta-analysis of the MMPI-2, a widely used instrument for detecting PIM, was conducted more than two decades ago. Method: Using a Robust Variance Estimation method, this meta-analysis synthesized the results of 27 studies that examined the MMPI-2 ( k =  22) and MMPI-2-RF ( k =  5) validity scales' ability to discriminate individuals who engage in PIM from genuine responders, with a particular focus on the L, K, and S scales. Results: The MMPI-2 L scale produced the largest effect size ( g =  1.30), whereas the MMPI-2-RF L-r scale effect size was moderate ( g  = 1.16). Moderate effect sizes were also found for the K ( g  = 1.01) and K-r ( g  = 1.21) scales, and for the MMPI-2 S scale ( g  = 1.23). Conclusions: Effect sizes did not significantly vary between the two versions of the MMPI. Findings suggest that both versions of the MMPI have demonstrated utility in identifying PIM, but clinicians should interpret T scores conservatively to account for the modest elevations associated with defensiveness. Findings are discussed in the context of the recently released MMPI-3.