Assessing the severity of challenging behaiour: psychometric properties of the Challlenging Behaviour Interview

Background The Challenging Behaviour Interview (CBI) was developed as an assessment of the severity of challenging behaviour. The CBI is divided into two parts. Part I of the interview identifies the occurrence of five clearly operationalized forms of challenging behaviour that have occurred in the last month. Part II of the interview assesses the severity of the behaviours identified on 14 scales measuring the frequency and duration of episodes, effects on the individual and others and the management strategies used by carers. In this paper we report upon its psychometric properties and discuss potential clinical and research uses of the new scale. Methods The CBI was administered to 40 adults and 47 children. Test-retest and inter-rater agreement was assessed for 22 participants in the adult sample. Concurrent validity was assessed by correlating total scores for the child sample with the subscale and total scores of the Aberrant Behavior Checklist (ABC). Content validity was assessed by comparing scores for each behaviour on specific items relating to relevant aspects of severity of impact that would be expected to differ based upon the topographies of the behaviour. Results Mean inter-rater and test-retest reliability kappa indices for the behaviours in Part I of the interview were 0.67 (range: 0.50-0.80) and 0.86 (range: 0.70-0.91), respectively. Mean inter-rater and test-retest reliability Pearson's correlation indices for the behaviours in Part II of the interview were 0.48 (range: 0.02-0.77) and 0.76 (range: 0.66-0.85), respectively. Correlations with the ABC varied between 0.19 and 0.68. The majority of content validity comparisons were in line with prediction. Conclusions The potential of the interview for clinical assessment, as an outcome measure for services and individual interventions and research purposes, is discussed.