Numerous constructs have been proposed to describe the transitional state between normal aging and dementia, but no one set of criteria is consistently referred to as the prodrome to dementia. Although there are many studies of the rates of these constructs, results are hampered by methodological differences. Research examining the overlap and stability of these constructs over time is also lacking, and predictive utility for later dementia remains inconclusive. Moreover, it is unknown whether one construct is superior in predicting later dementia or Alzheimer's disease. The current study addressed these issues using longitudinal clinical and neuropsychological data from a subsample (N=661) of participants in an epidemiological study of aging and dementia, the Cache County Memory Study (CCMS). Results confirmed wide variability in rates of preclinical dementia constructs. Constructs that included measures of functional impairment were the most stable, whereas constructs relying on memory impairment were generally unstable. Using bivariate logistic regression, four of the seven constructs were associated with later dementia, and these constructs either measured multiple cognitive domains or functional impairment. The 'Mild Ambiguous' construct, which includes memory or functional impairment, was statistically superior in predicting later dementia. Although four of the seven constructs were also significant predictors of later AD, no one construct was superior.