Measuring troublesomeness of chronic pain by location.

Background: Current measures of pain assess the relative contribution of pain in different body regions to the overall impact of pain. We developed a series of questions to measure the relative 'troublesomeness' of pain in different body regions (the "troublesomeness grid"). The study aimed to determine whether the "troublesomeness grid" is an appropriate measure to assess the severity of pain in different body regions, allowing the comparative severity of pain in different body regions to be assessed.

Methods: We used data from a pilot for a population survey of pain (N = 205) and from the population survey itself (N = 2504) to assess the 'troublesomeness grid's performance. Specifically, its face and content validity using overall and item non-completion rates; its criterion related validity by exploring the relationship between troublesomeness and standard measures of pain, disability, distress and health utility for the five body regions most commonly affected by chronic pain; and its reliability and reproducibility in a test/re-test study.

Results: The troublesomeness grid appeared to have good face validity as it had good completion rates. It also appeared to have good content validity as the percentage agreement between the grid and the pain manikin was high (over 90%). In terms of criterion related validity, troublesomeness was most strongly correlated with pain intensity and health related quality of life, but less with disability and distress. The test-retest reliability was between 80% and 90% for the majority of body regions examined.

Conclusion: The troublesomeness grid is well completed and appears to be an appropriate tool to assess the comparative severity of pain in different body regions.