Examining the stability of Automated Neuropsychological Assessment Metric (ANAM) baseline test scores

Abstract

Computerized neuropsychological (NP) testing has evolved into an important tool for clinicians in the assessment of sport-related concussions. The importance of having a reliable baseline test score for comparison post concussion is critical; yet, the stability of these baseline measurements has not been well established. The purpose of this study was to examine the consistency of the measurements derived from the Automated Neuropsychological Assessment Metric (ANAM) test battery over a series of repeated trials, in an attempt to determine at what point the test scores stabilized. A cohort of 25 recreationally active collegiate students, free from mild head injury, volunteered for the study. Throughput score (measures of performance efficiency) stability was assessed for the computerized NP tests using intraclass correlation coefficients (ICCs). Average throughput scores for all five test trials were simple reaction time (SRT) = 235, matching to sample (MSP) = 41, continuous performance test (CPT) = 108, math processing (MTH) = 24, and Sternberg memory (STN) = 89, and these are within the range of those previously reported. Results show that all four of the ICCs were in the excellent range of agreement (i.e., ≥ .75), and more importantly, the statistical comparisons of the ICCs show that there was no significant difference between the ICCs. Consequently, results serve to show that two time periods are sufficient to obtain stable NP results, and thus clinicians can feel comfortable relying on a two-score baseline test for follow-up comparison.