"Sandbagging" baseline test performance on ImPACT, without detection, is more difficult than it appears.

Participants coached to display poor effort on neuropsychological tests have successfully evaded detection. Recent research has documented that 89% college athletes instructed to perform poorly on a follow-up baseline ImPACT (Immediate Post-concussion Assessment and Cognitive Testing) test were unable to bypass detection, but otherwise, sandbagging on baseline testing has not been directly studied. In an analog study intended to measure participants' ability to successfully sandbag, we compared baseline test performance in three groups of individuals, instructed: (a) to perform their best, (b) to malinger without guidance (e.g., naïve), and (c) how to malinger (e.g., coached), using ImPACT, the Medical Symptom Validity Test (MSVT), and the Balance Error Scoring System. The MSVT identified more participants in the naïve (80%) and coached (90%) groups than those automatically "flagged" by ImPACT (60% and 75%, respectively). Inclusion of additional indicators within ImPACT increased identification to 95% of naïve and 100% of coached malingerers. These results suggest that intentional "sandbagging" on baseline neurocognitive testing can be readily detected.