title: Defining MCI in the Framingham Heart Study Offspring: education versus WRAT-based norms.
abstract: BACKGROUND
  Psychometric definitions of mild cognitive impairment (MCI) typically use cut-off levels set at 1.5 SDs below age-adjusted and education-adjusted norms, assuming that the education adjustment accounts for premorbid abilities. However, noncognitive factors impact educational attainment, potentially leading to incorrect categorization as MCI. We examined whether using an adjustment based on reading performance [Wide Range Achievement Test (WRAT) Reading] improved MCI diagnostic accuracy.
  
  
  METHODS
  A total of 935 Framingham Offspring (mean age, 72±5 y) underwent tests of memory, executive function, abstraction, language, and visuospatial function as part of a neuropsychological test battery. Domain-specific test scores were regressed onto age and WRAT score, or education, to define MCI. Survival analyses were used to relate baseline MCI to incident dementia.
  
  
  RESULTS
  The 2 MCI definitions differed most for the lowest and highest education groups. The WRAT definition was more strongly associated with incident dementia for all 5 tests. MCI level abstraction performance was associated with incident dementia using the WRAT definition (HR=3.20, P=0.033), but not the education definition (HR=1.19, P=0.814).
  
  
  CONCLUSIONS
  The WRAT should be considered along with the standard measure of years of education, as it may be a better surrogate marker of premorbid abilities.
authors: *Framingham Heart Study †Department of Neurology, Framingham Heart Study, Boston University School of Medicine ‡Department of Biostatistics, Boston University School of Public Health, Boston, MA.
authors: Richard E
authors: RE
authors: Ahl
authors: Alexa
authors: A
authors: Beiser
authors: Sudha
authors: S
authors: Seshadri
authors: Sanford
authors: S
authors: Auerbach
authors: Philip A
authors: PA
authors: Wolf
authors: Rhoda
authors: R
authors: Au
mesh_terms: D000368:Aged; D000369:Aged, 80 and over; D060825:Cognitive Dysfunction / Q000175:diagnosis* / Q000523:psychology*; D015331:Cohort Studies; D003430:Cross-Sectional Studies; D004522:Educational Status; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D008137:Longitudinal Studies; D008297:Male; D009483:Neuropsychological Tests; D011446:Prospective Studies; D011597:Psychomotor Performance / Q000502:physiology; D011932:Reading