Scores on the MMPI-2-RF scales as a function of increasing levels of failure on cognitive symptom validity tests in a military sample

This research examined associations between the full range of Minnesota Multiphasic Personality Inventory-2-Restructured Form (MMPI-2-RF) validity and substantive scales and increasing levels of cognitive symptom validity test (SVT) failure in a sample of 501 military members who completed a neuropsychological evaluation primarily for mild traumatic brain injury resulting from a closed head injury and blast exposure or heat injury. SVT failure was associated with significant linear increases in all of the over-reporting MMPI-2-RF validity scales and most of the substantive scales. For the validity scales, all over-reporting scales had large effect sizes (ESs) when comparing a group that failed no SVTs with a group that failed three SVTs. A comparison between these two groups for the substantive scales revealed the largest ESs for scales related to somatic/cognitive complaints and emotional dysfunction. RBS (Response Bias Scale) had the largest ES of all scales (d = 1.69), followed by FBS-r (Symptom Validity Scale; d = 1.34), AXY (Anxiety, d = 1.21), and COG (Cognitive Complaints, d = 1.19). The scales related to behavioral dysfunction had the smallest ESs of all of the substantive scales, and there were no significant associations between the vast majority of these scales and SVT failure. With respect to clinically significant elevations, those who did not fail SVTs had clinically significant elevations only on COG and NUC (Neurological Complaints), and MLS (Malaise) approached clinical significance. For those who failed SVTs, RBS was the only over-reporting scale that was elevated across all failure groups. Those who failed any SVT had clinically significant elevations on COG, MLS, NUC, and AXY. Those who failed three SVTs had additional elevations on scales related to emotional dysfunction.