Validation and adaptation of the Norwegian version of Hayes Ability Screening Index for intellectual difficulties in a psychiatric sample.

BACKGROUND: Intellectual disabilities (ID) among psychiatric patients have traditionally been neglected. A lack of convenient instruments and competency in ID may have worsened the conditions and treatment availability for these patients. AIMS: Validation and adaptation of a screening instrument for ID (Hayes Ability Screening Index; HASI) in a psychiatric hospital setting. METHODS: This is a cross-sectional study of 50 psychiatric patients in two Norwegian psychiatric hospitals comparing results of the HASI with the Wechsler Abbreviated Scale of Intelligence (WASI). RESULTS: The HASI correlated well with the standard IQ test used (r= 0.67, P< 0.001). At a stated cut-off score of 85, the HASI had a sensitivity of 100% and specificity of 34%. CONCLUSIONS: The HASI is a valid and time-saving screening instrument for ID among psychiatric patients. The prescribed cut-off score, however, resulted in a large number of false positives.