Abstract
The identification and management of persistent post-concussion symptoms (PPCS) is reliant on the accurate and valid reporting of symptoms. To assist with the evaluation of validity, symptom validity indicators (SVIs) are used. This study explored the utility of the newly developed modified Rivermead Post-concussion Symptoms Questionnaire (RPQ), which embeds an SVI into the RPQ (mRPQ). Ninety-four participants completed the mRPQ; two existing SVIs (the Validity-10 [Val-10] and the Mild Brain Injury Atypical Symptoms [mBIAS] scale); two performance validity tests (the Test of Memory Malingering [TOMM] and Warrington’s Memory Recognition Test [WMRT]); and, a post-experimental questionnaire. This study utilized a simulation design, with participants randomly allocated to one of two conditions: mTBI Simulator (MS, n = 47) or Biased mTBI Simulator (BMS, n = 47). The BMS group received an additional biasing instruction to motivate distorted responding for a forensic assessment context. The validity measures were highly intercorrelated, as were the PPCS scores (p < 0.05). There were significant group differences on all measures (p < 0.05). The BMS group reported more PPCS than the MS group, and showed more signs of invalidity. Although relatively new and requiring further analysis, this study shows the mRPQ has the potential to aid clinical assessment as an indicator of symptom invalidity.