The ABS is an observational as opposed to a self-report measure. Original validation studies showed that nursing staff, physical therapists and occupational therapists can use the scale reliably and validly. At Ohio State University, the ABS is completed by the primary nurse at the end of each shift. Ratings based on 10-minute observation periods by psychology assistants or a rehabilitation nurse have also been found to be reliable.
Observers make a rating of one to four for each of the fourteen items.
In validation, nurses and therapists were trained by sharing impressions and asking feedback during a trial-use period. Written descriptions of ratings for each item, with examples, are available from Drs. Corrigan and Bogner at Ohio State University.