title: The SIST-M: predictive validity of a brief structured clinical dementia rating interview.
abstract: BACKGROUND
  We have previously established the 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 the predictive validity of the SIST-M.
  
  
  METHODS
  Participants were 342 community-dwelling, nondemented older adults in a longitudinal study. Baseline 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+sex+education-adjusted Cox proportional hazards models using CDR-sum-of-boxes (CDR-SB) as the predictor, where CDR-SB was determined by either a clinician interview or an algorithm; models were run for the full sample (n = 342) and among those jointly classified as vMCI using clinician-based 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, the respective HRs [95% confidence interval (CI)] were 3.1 (2.5, 3.9) and 2.8 (2.2, 3.5); among those with vMCI, the 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 area-under-the-ROC curves) over follow-up was 0.78 versus 0.76 using clinician-based versus algorithm-based CDR-SB.
  
  
  CONCLUSIONS
  CDR scores based on items from this shortened interview had high predictive ability for AD-comparable to that using a lengthy clinical interview.
authors: Department of Psychiatry, Massachusetts General Hospital, Harvard Medical School, Boston, MA, USA. ookereke@partners.org
authors: Olivia I
authors: OI
authors: Okereke
authors: Norberto
authors: N
authors: Pantoja-Galicia
authors: Maura
authors: M
authors: Copeland
authors: Bradley T
authors: BT
authors: Hyman
authors: Taylor
authors: T
authors: Wanggaard
authors: Marilyn S
authors: MS
authors: Albert
authors: Rebecca A
authors: RA
authors: Betensky
authors: Deborah
authors: D
authors: Blacker
mesh_terms: D000368:Aged; D000465:Algorithms; D019540:Area Under Curve; D003704:Dementia / Q000175:diagnosis*; D005260:Female; D006801:Humans; D007407:Interviews as Topic / Q000379:methods*; D008297:Male; D008875:Middle Aged; D009483:Neuropsychological Tests; D011237:Predictive Value of Tests; D016016:Proportional Hazards Models; D011569:Psychiatric Status Rating Scales; D012372:ROC Curve; D015203:Reproducibility of Results