The Psychometric Qualities of Four Observational Pain Tools (OPTs) for the Assessment of Pain in Elderly People with Osteoarthritic Pain

Context: Pain in cognitively impaired elderly people (CIEP) often goes unrecognized. Observational pain tools (OPTs) have been designed, but with limited evidence to support their psychometric qualities.

Objectives: This study compared four OPTs (the Pain Assessment IN Advanced Dementia [PAINAD], Abbey Pain Scale [Abbey PS], Pain Assessment Checklist for Seniors with Limited Ability to Communicate [PACSLAC], and Discomfort Scale--Dementia of Alzheimer Type [DS-DAT]), two self-report scales, and two proxy-report scales in assessing osteoarthritic (OA) pain among CIEP.

Methods: Participants (n=124) were divided into two groups: cognitively intact and impaired. They were observed by two raters simultaneously at rest and during a standardized exercise program. Besides reliabilities, the correlation between the OPTs and the self-report/proxy-report scores was evaluated. The OPT scores collected during different activity levels were compared to establish the convergent and discriminant validity. Confirmatory factor analysis was used to evaluate the construct validity.

Results: Similar and accepted patterns of reliability/validity were obtained for all OPTs, in which better levels of psychometric properties were consistently obtained during exercise. However, a single construct (OA pain) appeared only in the PAINAD and Abbey PS after deletion of the "breathing" and "physiological change" indicators, respectively. This showed that OPTs were better used to detect OA pain when pain was triggered by movement (i.e., an exercise program).

Conclusion: The PAINAD and Abbey PS appeared to be more reliable and valid for assessing OA pain while using an exercise program among elderly people, regardless of their cognitive ability.