Brief iPad-Based Assessment of Cognitive Functioning with ImPACT® Quick Test: Prevalence of Low Scores Using Multivariate Base Rates.

OBJECTIVE

The ImPACT® Quick Test is a brief iPad-based battery of neurocognitive tests that has been standardized on a sample of children, adolescents, and adults (ages 12-70). This study provides information on the prevalence of ImPACT® Quick Test scores falling below specific percentiles in the normative sample to aid in clinical interpretation and reduce the risk of over-interpreting, or misinterpreting, a single low score.

METHOD: Participants were 683 individuals ranging in age from 12 to 70, who were assessed individually. The ImPACT® Quick Test includes five subtests, contributing to three factor scores: motor speed, memory, and attention tracker. The prevalence of low factor scores, stratified by age and sex, were calculated using multivariate base rates.

RESULTS

In the total sample, obtaining 1 or more scores below the 25th percentile was common (base rate, BR = 47.2%), but obtaining 2 or more scores in this range was uncommon (BR = 15.3%). Similarly, obtaining 1 or more scores below the 16th percentile was common (BR = 31.4%), but obtaining two or more scores in this range was uncommon (BR = 6.9%). There were small differences in BRs between sexes and the number of low scores was fairly similar across the age groups.

CONCLUSION

Results from this study parallel previous work illustrating that a substantial percentage of healthy individuals will obtain one or more low test scores when administered a brief battery of cognitive tests. Given that some healthy individuals will obtain a single score below expected cut-offs, clinicians should caution against overinterpreting a single low test score.