title: The time and change test: a simple screening test for dementia.
abstract: BACKGROUND
  Although dementia screening tests are available, they have not gained widespread use in hospital or primary care settings. Our goal was to develop a simple, standardized, performance-based test incorporating real-world activities to augment screening efforts in older populations: the Time and Change (T&C) Test.
  
  
  METHODS
  The study followed a prospective cohort design, involving medicine and surgery services at an urban teaching hospital. From consecutive admissions, 776 participants aged 70-98 years, 14% with dementia, were enrolled. T&C ratings were validated against a reference standard based on the modified Blessed Dementia Rating Scale and the Mini-Mental State Examination (MMSE). Convergent validity with other cognitive measures, test-retest agreement, and interobserver reliability were assessed.
  
  
  RESULTS
  The T&C Test had a sensitivity of 86%, specificity of 71%, and negative predictive value of 97%. The T&C Test demonstrated convergent agreement with three cognitive measures, agreeing most strongly with the MMSE (r = .58). Test-retest and interobserver agreement rates were 88% and 78%, respectively. Education explained 3% of the variance of the T&C Test, compared with 13% of the MMSE. The T&C Test took a mean of 22.9 seconds to complete and was acceptable to participants. Refusal of any test component occurred in 39 individuals (5%).
  
  
  CONCLUSIONS
  The T&C Test is a simple, accurate, reliable, performance-based tool for detection of dementia. With its quick, easy-to-use, real-world nature, we hope the T&C Test will be used for widespread cognitive screening in older populations.
authors.affiliation: Department of Internal Medicine, Yale University School of Medicine, New Haven, CT 06504, USA.
authors.forename: S K
authors.initials: SK
authors.lastname: Inouye
authors.forename: J T
authors.initials: JT
authors.lastname: Robison
authors.forename: T E
authors.initials: TE
authors.lastname: Froehlich
authors.forename: E D
authors.initials: ED
authors.lastname: Richardson
mesh_terms: D000203:Activities of Daily Living / Q000145:classification; D000368:Aged; D000369:Aged, 80 and over; D000554:Ambulatory Care Facilities / Q000706:statistics & numerical data; D003237:Connecticut / Q000453:epidemiology; D003704:Dementia / Q000175:diagnosis* / Q000453:epidemiology; D005260:Female; D015577:Geriatric Assessment / Q000706:statistics & numerical data*; D006801:Humans; D015994:Incidence; D016014:Linear Models; D008297:Male; D008609:Mental Status Schedule; D011320:Primary Health Care; D011446:Prospective Studies; D011594:Psychometrics; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity