Comparing the test of practical judgment with the neuropsychological assessment battery judgment subtest in a neurodegenerative disease clinic population

The Test of Practical Judgment (TOP-J) and the Judgment subtest from the Neuropsychological Assessment Battery (NAB-JDG) are both brief interview-based measures that assess judgment. This study compared estimates of judgment obtained from these measures in a neurodegenerative disease population. Records from 61 referrals seen for neuropsychological evaluation in a neurodegenerative disorders clinic were reviewed. Measures of interest included the TOP-J and NAB-JDG. Concordance correlation coefficients (CCC) and root mean square differences (RMSD) were calculated between judgment T-scores. Discrepancy scores were calculated by subtracting NAB-JDG scores from TOP-J scores. CCC showed poor agreement between the judgment measures, with evidence of fixed bias, such that the NAB-JDG systematically generates higher scores than the TOP-J. This fixed bias was present whether NAB-JDG scores are demographically adjusted or unadjusted. There was no evidence of proportional bias. In a neurodegenerative disease clinic population, the TOP-J and NAB-JDG provide estimates of judgment ability that are systematically different. These two measures may be assessing different aspects within the larger construct of judgment and the inconsistency between measures would contraindicate using them interchangeably. Clinicians will need to carefully consider patient characteristics, clinical needs, and review specific item content when selecting between these measures.