The prediction of change: normative neuropsychological trajectories

While the application of normative standards is vital to the practice of clinical neuropsychology, data regarding normative change remains scarce despite the frequency of serial assessments. Based on 285 normal individuals, we provide co-normed baseline data with demographic adjustments and test-retest standardized regression based (SRB) models for three time points for several measures. These models delineate normal, expected change across time, and yield standardized z-scores that are comparable across tests. Using a new approach, performance on any previous trial was accounted for in the subsequent models of change, yielding serial normative formulas that model change trajectories rather than simple change from point to point. These equations provide indices of deviation from expected baseline and change for use in clinical or research settings.