The use of a self-reported pain measure, a nurse-reported pain measure and the PAINAD in nursing home residents with moderate and severe dementia: a validation study

Objectives: to assess the construct validity of three measures of pain and to determine a categorical version of the Pain Assessment in Advanced Dementia (PAINAD) scale. Design: validation study determining the concurrent validity of a self-reported pain score (SRPS), a nurse-reported pain score (NRPS) and the PAINAD; the divergent validity of the three pain measures with the Abbreviated Mental Test (AMT) and the Cornell Scale for Depression in Dementia (CSDD). Setting and subjects: eighty-eight nursing home residents with moderate and severe dementia. Methods: residents were asked to rate the severity of their pain in the previous week on a verbal descriptor scale (VDS). Nurses rated the resident's pain on a VDS, scored the PAINAD scale and the CSDD scale. Research assistants administered the AMT. Results: the PAINAD correlated with the NRPS (Kendall's tau [tau] = 0.842); both scales correlated poorly with the SRPS (tau = 0.304 for both correlations). The PAINAD was significantly different for each level of the NRPS. On the SRPS, the PAINAD for the group with moderate+ pain was significantly different from the groups with mild pain and no pain. There was a difference between the SRPS and the NRPS when residents were depressed, but no difference when they were not. Our categorical version of the PAINAD showed good agreement with the NRPS. Conclusion: the NRPS and the PAINAD measure pain differently from the SRPS, especially in the presence of depression. Our categorical version of the PAINAD shows good agreement with the NRPS.