Comparison of the Diagnostic Validity of Real and Absolute Skin Temperature Differences for Complex Regional Pain Syndrome

Background: A skin temperature difference is one of the variables used in the diagnosis of complex regional pain syndrome. However, there have been no reports as to whether the real (T) or absolute value () of skin temperature differences should be used in the diagnosis of complex regional pain syndrome. This study was conducted to compare the diagnostic validity of T with for complex regional pain syndrome using receiver operating characteristic curves (ROC). Methods: Infrared thermographic images were obtained from the 144 patients who were suspected to have CRPS in a unilateral limb. After T and calculation from the thermographic image, ROCs of T and were developed, and the areas under the curve (AUC) for the ROC curves were compared. Results: AUCs of T and were 0.520 and 0.746 respectively, this difference was statistically significant (P ＜ 0.001). Conclusions: Absolute skin temperature difference shows greater validity in the diagnosis of CRPS than T. Therefore, is more useful when comparing the skin temperature of CRPS patients.