Pain measurement in elders with chronic low back pain: traditional and alternative approaches

Pain evaluation typically relies upon the use of self-report instruments. The validity of these tools is questionable in many older adults, however, particularly those with cognitive impairment. Rating of pain behavior (e.g. grimacing, sighing) by an objective observer represents an alternative pain assessment strategy which has been validated in subjects of heterogeneous ages. The purpose of this study was to examine, in a group of community-dwelling elderly with low back pain and lumbosacral osteoarthritis, the concurrent validity of observational pain behavior rating techniques as compared with self-report instruments and the degree to which pain and pain behavior relate to disability. Thirty-nine cognitively intact subjects, age > 65 years, without depression, other sources of pain, or other known spinal pathology underwent the following measures: (1) pain self-report using the verbal 0-10 scale, vertical verbal descriptor scale, Arthritis Impact Measurement Scales and McGill Pain Questionnaire; (2) pain behavior was sampled during two protocols, one, identical to that used by Keefe and Block (Behav. Ther., 13 (1982) 363-375), that required subjects to sit, stand, walk, and recline for 1-2 minute periods (which we have labelled the traditional protocol), and a second, more demanding protocol that was designed to simulate activities of daily living that place a premium on axial movement (the 'ADL' protocol); (3) disability was assessed using the Roland questionnaire, a 6 month global disability question and the Jette Functional Status Index; and (4) radiographic evaluation of the lumbosacral spine; osteoarthritis was quantitated using a previously validated scoring system. Interrelationships among pain, pain behavior and disability measures were tested using canonical correlations. Self-reported pain was associated with pain behavior frequency; the association was stronger when the ADL protocol was used, as compared with the traditional protocol. The association between pain and disability was modestly strong with both self-report instruments and pain behavior observation when the ADL protocol was used, but not when the traditional protocol was used. Our findings suggest that pain behavior observation is a valid assessment tool in the elderly. In addition, it seems that observation of elders during performance of activities of daily living may be a more sensitive and valid way of assessing pain behavior than observing pain behavior during sitting, walking, standing, or reclining.