Background: The aim of this study is to evaluate aspects of inter-rater reliability of the Perceive, Recall, Plan, and Perform (PRPP) system of task analysis for assessing daily functioning of home-dwelling dementia patients.
Method: Videotaped recordings of 30 German patients with dementia performing a relevant daily task in their own homes were scored independently by ten Dutch PRPP trained occupational therapists, randomly selected from a pool of 25. Intra-class correlations (ICC) (one-way single measure) were calculated for PRPP Stage One independence score, and PRPP Stage Two information processing scale, quadrant scales, and subquadrant scales from a total of 300 PRPP scores.
Results: ICCs for Stage One PRPP independence score were good to excellent (0.63; 0.94) for both individual rater and test reliability. The Stage Two PRPP total score showed moderate correlations (0.46) for the single rater absolute agreement and excellent agreement (0.90) for test reliability. The four quadrant scale scores of the PRPP showed limited single rater absolute agreement (0.37–0.39) but excellent average test agreement (0.85–0.87). All subquadrants of information processing showed limited single rater absolute agreement (0.26–0.38) and good to excellent average test agreement (0.78–0.86). This suggests that the PRPP total is reliable in assessing information processing during activity performance in dementia patients.
Conclusions: The PRPP is a reliable measure to evaluate individual performances of routines and tasks in community-living dementia patients by multiple raters. Future research should address reliability and validity features of the PRPP for dementia patients with incorporation of criterion-referenced test characteristics.