The McGill Pain Questionnaire in patients with TMJ pain and with facial pain as a somatoform disorder

The purpose of this study was to assess the discriminative capacity of the McGill Pain Questionnaire (MPQ) in patients with temporomandibular joint di sorders (TMD) or with facial pain disorder as somatoform disorder (referred to as "atypical facial pain") (FP), The MPQ was administered to 57 TMD and 34 FP patients. Weighted MPO item scores, subscale Pain Rating indexes (PR I), and total Pain Rating Index were tested for significant differences (St udent's t-test), and the frequency of descriptor choice was also analyzed. Furthermore, the data were processed through two systems based on a counter -propagation neural network: the Self-Organizing Map (SOM) system and a clu ster-like analysis, In the FP group eleven MPQ item scores and five PRI sco res were significantly higher than those of the TMJ group, There was a cons iderable difference in descriptor choice between the groups. SOM analysis a nd cluster-like analysis correctly discriminated 85% or more of the patient s. In conclusion, the MPQ showed a consistent discriminative capacity betwe en TMD and FP patients.