The SIST-M

Olivia I. Okereke, Norberto Pantoja-Galicia, Maura Copeland, Bradley T. Hyman, Taylor Wanggaard, Marilyn S. Albert, Rebecca A. Betensky, Deborah Blacker
2012 Alzheimer Disease and Associated Disorders  
Background-We previously established reliability and cross-sectional validity of the SIST-M (Structured Interview and Scoring Tool-Massachusetts Alzheimer's Disease Research Center), a shortened version of an instrument shown to predict progression to Alzheimer disease (AD), even among persons with very mild cognitive impairment (vMCI). Objective-To test predictive validity of the SIST-M. Methods-Participants were 342 community-dwelling, non-demented older adults in a longitudinal study.
more » ... e Clinical Dementia Rating (CDR) ratings were determined by either: 1) clinician interviews or 2) a previously developed computer algorithm based on 60 questions (of a possible 131) extracted from clinician interviews. We developed age+gender+education-adjusted Cox proportional hazards models using CDR-sum-of-boxes (CDR-SB) as the predictor, where CDR-SB was determined by either clinician interview or algorithm; models were run for the full sample (n=342) and among those jointly classified as vMCI using clinician-and algorithm-based CDR ratings (n=156). We directly compared predictive accuracy using time-dependent Receiver Operating Characteristic (ROC) curves. Results-AD hazard ratios (HRs) were similar for clinician-based and algorithm-based CDR-SB: for a 1-point increment in CDR-SB, respective HRs (95% CI)=3.1 (2.5,3.9) and 2.8 (2.2,3.5); among those with vMCI, respective HRs (95% CI) were 2.2 (1.6,3.2) and 2.1 (1.5,3.0). Similarly high predictive accuracy was achieved: the concordance probability (weighted average of the areaunder-the-ROC curves) over follow-up was 0.78 vs. 0.76 using clinician-based vs. algorithmbased CDR-SB. Conclusion-CDR scores based on items from this shortened interview had high predictive ability for AD -comparable to that using a lengthy clinical interview.
doi:10.1097/wad.0b013e318231cd30 pmid:21986342 pmcid:PMC3257375 fatcat:qogluhcupffllh7agg5y4ihxny