Evaluation of reliability, validity, and preference for a pain intensity scale for use with the elderly

The main objective of this research was to determine the initial psychometric properties of the Spanish Version of the Faces Pain Scale-Revised (FPS-R) as a measure of pain intensity for use with the elderly. To assess the scaling properties, validity, and reliability of the FPS-R, a total sample of 177 subjects aged 65 years or older participated in this study. Ranking procedures, placement tasks, and test-retest methods were used. The participants were asked to rate their pain intensity by using the FPS-R and a pain thermometer (PT) and to inform about their affective state. They were also asked to imagine themselves in 5 hypothetical painful situations (Geriatric Painful Events Inventory) and rate the degree of pain by using the FPS-R and the PT at 2 different times. Rank ordering tasks for the individual faces showed excellent agreement between the expected ranking and the one provided by the participants (Kendall's W = 0.75, P <.0001). The pain intensity ratings reported with FPS-R and the PT were very similar, and the relationship between the intensity of pain experienced and participant's negative affective state was statistically significant (r = 0.32, P <.01). Test-retest correlations on the Geriatric Painful Events Inventory ranged from 0.44 to 0.7. All the participating subjects were asked to choose the pain scale they preferred. Our data suggest that, regardless of their age and/or gender, the subjects preferred the FPS-R to the PT. Overall, these results provide preliminary evidence of its reliability and convergent and criterion-related validity as well as its strong ordinal properties with a sample of elderly subjects. Perspective: This article presents the evaluation of reliability, validity, and preference for a pain intensity scale for use with the elderly, the Faces Pain Scale-Revised. This scale could help clinicians to assess the intensity of pain in cognitively intact elderly patients and might also be helpful in making decisions about treatment. Likewise, it could be used by researchers who wish to evaluate the effects of available treatments. (c) 2005 by the American Pain Society.