A new simple score (ABS) for assessing behavioral and psychological symptoms of dementia
A rating scale for assessing troublesome behavior associated with dementia illnesses was developed. This instrument, named the troublesome behavior scale (TBS), is designed to be completed by family and professional caregivers. It is comprised of 14 questions assessing a variety of types of disruptive or burdensome behavior. Two of the 14 questions differ in their assessment for outpatients and that for inpatients. Each of the 14 items is rated with 5 possible responses corresponding to the frequency of the behavior in the preceding month (from 0 = never, to 4 = once every day or more). Thus, higher scores indicate more disturbance. The TBS was administered to 146 outpatients and 167 inpatients with dementia based on the DSM III-R criteria in order to test its reliability and validity. The data were analyzed separately for outpatients and inpatients. The reliability of the scale, based on calculation of perfect agreement rates and kappa values, indicated high test-retest and inter-rater reliability for both samples. Validity, by confirmatory factor analysis of the data from the outpatients, revealed three main factors, namely, "behavior toward caregivers", "self-absorbed behavior" and "elaborate behavior". The same analysis of data from inpatients resulted in a different set of three factors: "behavior interfering with care work", "behavior necessitating watchful protection" and "behavior resulting in missing articles". From these findings TBS appears to be a reliable and valid instrument for assessing troublesome behavior of patients with dementia.