Rating scale analysis of the Agitated Behavior Scale

Objective: Evaluate the measurement properties of the Agitated Behavior Sca le (ADS) using rating scale analysis. Samples: Sample 1: 900 observations o f 100 individuals with traumatic brain injury; Sample 2: 204 observations o f 102 persons with dementia: Sample 3: 241 observations of 6 individuals wi th anuria. Results: The calibration indicated that the raring scale was use d as intended. The hierarchies of item difficulty were similar across sampl es. Person and item separation values were within the acceptable range for the TBI sample, Generally, the items work well together, however 3 items mi sfit the measurement model moderately. Conclusions: Agitation as measured b y the ABS is best represented as a unitary construct. Results provide addit ional support for the reliability and validity of the ABS.