Psychometric properties of the ABSI-id, an adapted measure for anger-related interoceptive awareness in individuals with mild intellectual disabilities or borderline intellectual functioning

Background: The present study examined the psychometric properties of the Anger Bodily Sensations Interview - intellectual disabilities (ABSI-id), an adapted instrument to measure anger-related interoceptive awareness (IA) in individuals with mild intellectual disabilities or borderline intellectual functioning (MID-BIF). Method: The ABSI-id was individually administered to 208 clients (51% male) with MID-BIF in residential facilities. Results: An EFA and CFA showed a two-factor structure of the ABSI-id, including nine items. The ABSI-id had moderate to good reliability, with an internal consistency ranging from acceptable to good, a test-retest reliability ranging from moderate to good and an adequate convergent validity. There was no significant difference in ABSI-id scores between individuals with MID and BIF. Conclusion: The ABSI-id is a promising instrument for measuring anger-related IA, additional research is needed on validity and sensitivity of change.