The utility of a burn specific measure of pain anxiety to prospectively predict pain and function: a comparative analysis

Patients treated for burn injuries commonly experience high levels of acute pain and anxiety during hospitalization, particularly as it relates to their dressing changes and other medical procedures. A new instrument, the burn specific pain anxiety scale (BSPAS), was designed to characterize patient's anxiety in this setting, but its predictive validity in relation to other measures of anxiety has yet to be demonstrated. In this study, 27 patients with acute burn injuries completed three measures of anxiety upon admission to a major medical burn trauma center. Scores on the anxiety measures were compared with regard to their ability to predict subsequent ratings of procedural and background pain levels, pain medication usage, and physical and emotional functioning upon discharge. In support of criterion-related validity, the BSPAS was the best predictor of procedural pain levels as rated later the same day relative to the other global anxiety measures; moreover, the BSPAS did not predict later-day background pain levels as hypothesized. Both the BSPAS and the global anxiety measures were found to significantly predict total number of pain medications over a 24-h period. Finally, the BSPAS was the only significant predictor of decreased physical role functioning at discharge whereas the other more global measures of anxiety were better predictors of emotional functioning. These results provide preliminary evidence that the BSPAS is a unique and valid indicator of pain-related anxiety surrounding burn care in hospitalized patients and may be useful in identifying those patients at risk for decreased functional capacity at the time of discharge.