Generic Pain Intensity Scores Are Affected by Painful Comorbidity

Aims: To determine the degree to which the generic pain intensity rating (ie, overall and without reference to a particular body site) of facial pain patients being seen in a specialty setting for facial pain is influenced by painful comorbidity in body parts other than the face. Methods: In this prospective study, 40 consecutive female temporomandibular pain patients rated their generic pain on a 100-mm visual analog scale. After marking all painful body sites on pain drawings, patients were asked to rate the pain intensity for each of the indicated pain sites; the patients did not have access to the generic pain intensity score. Pearson's correlation coefficient was used to correlate the generic pain intensity score with site-specific pain intensity ratings, their mean and maximum, and the number of pain sites. Results: The medians of the generic, maximum, and facial pain intensity scores were 49.5, 53, and 45.5, respectively. The generic pain intensity rating correlated more highly with the intensity scores reported for the most painful body site (r2 = 0.82; P 0.001) than with the average rating across all painful sites (r2 = 0.62; P 0.001), or the pain intensity score in the face (r2 = 0.61; P 0.001). The number of pain sites did not correlate to any statistically significant degree with the generic pain intensity rating (r2 = 0.006; P = 0.65). Conclusion: The results of this study suggest that the maximum visual analog scale pain intensity score, observed in any body location, is a better reflection of the generic pain intensity rating than the corresponding score of the face. To avoid overrating or underrating of facial pain intensity, patients should be instructed to provide site-specific pain intensity scores if painful comorbidity is present.