Cross‑Validating the Atypical Response Scale of the TSI‑2 in a Sampleof Motor Vehicle Collision Survivors

This study was designed to evaluate the utility of the Atypical Responses (ATR) scale of the Trauma Symptom Inventory – Second Edition (TSI-2) as a symptom validity test (SVT) in a medicolegal sample. Archival data were collected from a consecutive case sequence of 99 patients referred for neuropsychological evaluation following a motor vehicle collision. The ATR’s classification accuracy was computed against criterion measures consisting of composite indices based on SVTs and performance validity tests (PVTs). An ATR cutoff of ≥ 9 emerged as the optimal cutoff, producing a good combination of sensitivity (.35-.53) and specificity (.92-.95) to the criterion SVT, correctly classifying 71–79% of the sample. Predictably, classification accuracy was lower against PVTs as criterion measures (.26-.37 sensitivity at.90-.93 specificity, correctly classifying 66–69% of the sample). The originally proposed ATR cutoff (≥ 15) was prohibitively conservative, resulting in a 90–95% false negative rat...