The prevalence and correlates of scores falling below ImPACT embedded validity indicators among adolescent student athletes

Objective: Valid performance on preseason baseline neurocognitive testing is essential for accurate comparison between preseason and post-concussion test results. Immediate Post-Concussion and Cognitive Testing (ImPACT) is commonly used to measure baseline neurocognitive function in athletes. We examined the prevalence of invalid performance on ImPACT baseline testing and identified correlates of invalid performance. Method: The sample included 66,998 adolescents (ages 14-18, M = 15.51 years, SD = 1.22) who completed ImPACT baseline tests between 2009 and 2019. Invalid performance was determined by the embedded validity indicators (EVI). Associations between invalid performance, demographic characteristics, and health conditions were assessed using chi-square tests and odds ratios (ORs). Results: Overall, 7.2% of adolescents had baseline tests identified as invalid by one or more of the EVIs. Individual validity indicators classified between 0.5% and 3.7% tests as invalid. Higher frequencies of invalid scores were observed among youth with neurodevelopmental, academic, and medical conditions. Youth who reported having learning disabilities (n = 3126), receiving special education (n = 3563), or problems with attention-deficit/hyperactivity disorder (ADHD; n = 5104) obtained invalid baselines at frequencies of 16.4%, 16.0%, and 11.1%, respectively. Moreover, youth who reported receiving treatment for a substance use disorder (n = 311) or epilepsy (n = 718) obtained invalid baselines at frequencies of 17.0% and 11.1%, respectively. Conclusions: The base rate of invalid performance on ImPACT's EVIs was approximately 7%, consistent with prior research. Adolescents self-reporting neurodevelopmental conditions, academic difficulties, or a history of treatment for medical conditions obtained invalid baseline tests at higher frequencies. More research is needed to better understand invalid scores in youth with pre-existing conditions.