The PTSD checklist for DSM-5 (PCL-5) symptom severity validity scale detects symptom overreporting among adult civilian neuropsychological outpatients

<b>Introduction</b>: This study expanded on prior literature by evaluating the classification accuracy of an embedded symptom validity test (SVT) within the PTSD Checklist for the DSM-5 (PCL-5), the PCL-5 Symptom Severity (PSS) SVT, in a civilian population referred for outpatient neuropsychological evaluation due to attention complaints. Moreover, this study examined the effect of elevated risk for posttraumatic stress, as defined by ≥4 adverse childhood events (ACEs), on optimal cutoffs. <b>Methods</b>: 496 adult patients evaluated at an academic medical center were included. Several criterion groupings (i.e. valid, possible overreporting 1/2/3 elevations, definite overreporting), were created using the five Minnesota Multiphasic Personality Inventory-2-Restructured Form/Multiphasic Personality Inventory-3 overreporting validity scales. The valid group was further divided into high (≥4 ACEs) or low (<4 ACEs) prior risk for posttraumatic stress. Receiver operating characteristic analyses determined classification accuracy across groups. <b>Results</b>: The PSS reached adequate classification accuracy in all groupings. Regardless of possible versus definite classification, a cutoff of ≥39 was optimal. However, in those with more trauma exposure and higher risk for PTSD (i.e. high-ACEs), a higher cutoff of ≥41 was needed, while a lower cutoff of ≥34 was needed for the low-risk group. Finally, supplemental analysis comparing definite to possible symptom overreporting further increased the cutoff to ≥55. <b>Conclusions</b>: This study extended the use of the PSS to broader civilian populations. However, the current variability of cutoffs with prior literature examining veteran samples suggests the need to replicate in samples with high base rates of PTSD.