Correction for a potentially biased item on the Mattis dementia rating scale

The Mattis Dementia Rating Scale (MDRS) is a multidimensional cognitive measure popular with clinicians for its brevity, diagnostic validity, and utility in monitoring impairment severity. In spite of the test's significant value, one task can cause discomfort because the patient is asked to name items the examiner is wearing. This task also creates possible cultural bias and standardization issues. We studied 102 MDRS profiles that included this item. Adjusted scores were calculated by giving all patients full credit for the apparel-naming item. The average adjustment was just one point, and the resulting dementia-severity ratings remained unchanged in 97% of the patients. These results show that administration of the item can be defensibly skipped if there is concern about its appropriateness with an individual patient. The adjusted scores provide a viable and fair alternative that preserves the psychometric properties of this useful instrument.