Ivnik, Robert J.

Two interpretations of the Boston Naming Test (BNT) discontinuation rule of "six consecutive failures" were uncovered in an informal survey. The rigorous interpretation includes correct responses to phonemic cues in the count of failures, whereas the lenient interpretation does not. Using both methods to score the same protocols, BNT final scores were changed in 3% of 655 normal elderly persons and in 31% of 140 patients with Alzheimer's Disease (AD). Among normals, discrepant scores were most often found in persons age 80 years and older, and scores differed by up to 16 points. Among AD patients, discrepant scores did not preferentially occur in any age group, but scores differed by up to 10 points. The clinical impact of BNT scoring differences occasionally can be substantial and warrants attention.

This study investigated the psychometric properties of the Mattis Dementia Rating Scale (DRS), including its internal consistency, sensitivity to age and education effects, pattern of change scores, convergent validity and predictive utility. Age and education effects and stability were assessed in a sample of 280 cognitively normal persons over age 55. All other features were assessed in a sample of 274 persons with cognitive impairment, including 221 newly diagnosed dementia patients and 53 patients with mild cognitive impairment. Both samples were drawn from the Mayo Clinic Alzheimer's Disease Patient Registry. Within the normal sample, Pearson correlation coefficients for DRS Total score with age, education and intelligence were all significant, p < .0001; MAYO Full Scale IQ (FSIQ) shared approximately 20% variance with DRS Total score. Internal consistency was greater than .7 for Construction, Conceptualization, Memory, and Total score, greater than .65 for Attention and less than .5 for Initiation and Perseveration. DRS subscales cores for Memory, Attention, and Conceptualization were significantly correlated with appropriate indices from the WAIS-R or Wechsler Memory Scale-Revised, as assessed in the Mayo Older Americans Normative Studies, providing convergent validity for these DRS scales. Importantly, proportional hazards modeling revealed initial DRS Total score to be a significant predictor of longitudinal institutionalization and mortality outcomes.