Reynolds Intellectual Screening Instrument 1st versus 2nd Edition in a Memory Disorder Sample

Objective: The Reynolds Intellectual Screening Instrument (RIST) and its second edition (RIST-2) are brief intelligence screening instruments that potentially have value in older populations as their norms extend over age 90. This study examined performance on these two instruments in a sample of individuals presenting for evaluation in a memory disorder clinic. Method: A sample of 1,145 subjects over the age of 50 was chosen from 1,761 consecutive referrals. Individuals who obtained a consensus diagnosis of Mild Cognitive Impairment (MCI; n = 536), possible dementia of the Alzheimer Type (DAT; n = 400), or those with subjective cognitive complaints (SCC; n = 209) and who completed a neuropsychological battery that included either the RIST (n = 747) or the RIST-2 (n = 398) were included in the sample. No clinically significant demographic or neuropsychological performance differences were found for those taking either version of the RIST. Results: Unlike the original version, RIST-2 Total and subtest scores were well below the mean for the DAT group and over 1 SD mean difference was seen for the DAT group when comparing the RIST and RIST-2 Totals. Diagnostic accuracy calculations suggested that the RIST-2 showed greater discrimination between the three groups although both versions achieved greater sensitivity than specificity. Conclusions: Performance differences were evident when comparing the RIST and RIST-2, particularly for the DAT group. Although the RIST-2 evidenced greater diagnostic accuracy than its predecessor it should not be utilized in isolation for the clinical determination of DAT or MCI.