Prevalence of behavioral symptoms: comparison of the minimum data set assessments with research instruments.

OBJECTIVE To examine the total and domain-specific prevalence of verbally and physically abusive, socially inappropriate, and care-resistive behaviors according to the Minimum Data Set (MDS) compared with research instruments in nursing home residents with severe dementia. DESIGN, SETTING, AND METHODS As part of a longitudinal observational study, MDS behavioral symptoms data were compared with corresponding items from the Ryden Aggression Scale and the Cohen-Mansfield Agitation Inventory for 15 nursing home residents with severe dementia. McNemar's test was used to compare the difference in the proportion of subjects who experienced any symptoms, as well as specific symptoms in several domains, according to the MDS and the research instruments. Additionally, temporal fluctuations in behavioral symptoms were descriptively and graphically summarized. RESULTS The MDS significantly underestimated both the total proportion of subjects experiencing any behavioral symptoms (P = .016), as well as the proportion of subjects experiencing verbally abusive symptoms (P < .002), physically abusive symptoms (P = .008), or socially inappropriate behaviors (P = .016) compared with corresponding items from the research instruments. Moreover, these behaviors exhibited considerable temporal instability, suggesting that the systematic daily collection of measures of behavioral disturbances is imperative during the week in which the MDS assessment is to be completed. DISCUSSION Albeit from a small study sample, our findings call into question the validity of the MDS behavioral symptom items as they are currently recorded, and suggest that a simple intervention of twice daily completion of a behavioral symptoms checklist containing the MDS items during the week of the assessment may significantly improve the accuracy of the recorded data.