Activities of daily living: reliability and validity of gross vs specific ratings.

The inter-rater reliability and criterion validity of gross vs specific ratings of activities of daily living (ADL) were compared. Forty-three physical therapy students rated 6 patients performing 16 ADL on videotape. With controls for tape order presentation and order of protocol use, specific ratings were found to be more reliable than gross ratings in terms of total scores, transfers, and personal hygiene activities. Dressing activities were found to be reliably rated on both protocols, but locomotion activities presented problems on both. In terms of criterion validity, both protocols significantly differentiated dependent, middle-range, and independent patients, but the gross ratings were significantly lower for dependent and middle-range patients than specific protocols. It was concluded that when activities can be broken down into independent task components, specific protocols are the assessment method of choice. When activities are made up of highly interdependent task components, a behaviorially anchored gross rating protocol may be more effective. Implications for further research are discussed.