A meta-analysis of the Miller Forensic Assessment of Symptoms Test (M-FAST).

The Miller Forensic Assessment of Symptoms Test (M-FAST) is a screening instrument created to assess for potential malingering. The aim of this study was to conduct a meta-analysis to evaluate the extent to which the M-FAST total score can differentiate overreporters from comparison groups. Research reports were located through searching databases (e.g., PsycINFO) and the M-FAST published manual. A random-effects model was used with Hedges' g as the effect size to represent the difference between the overreporting and comparison groups' M-FAST total scores. Twenty-one research reports were included in the meta-analysis, providing 25 effect sizes with nonoverlapping samples. A very large effect size was observed (g = 2.26, 95% CI [1.91, 2.62]), indicating a substantial difference on the M-FAST total score between the two groups. Moderator analyses were conducted to identify characteristics that might explain effect size variability. A significant difference was found between effect sizes that were part of the M-FAST development (g = 3.82, 95% CI [2.82, 4.82]) and effect sizes independent from its development (g = 2.03, 95% CI [1.70, 2.36]). Using 12 research reports, random-effects analyses found an average sensitivity of 0.83 and average specificity of 0.85 for the M-FAST total score at the cut-off of ≥ 6. Based on the findings, research performed independently from the M-FAST development should be consulted when evaluating the validity of the total score interpretations. Because it is a screening instrument, an examinee should not be classified as malingering from the results of the M-FAST total score alone. (PsycINFO Database Record (c) 2019 APA, all rights reserved).