Classification of clinical pain descriptions by multiple group discriminant analysis

Abstract

The McGill Pain Questionnaire, which consists primarily of verbal descriptions of pain qualities, was administered to 95 patients suffering from one of eight known pain syndromes. In a multiple group discriminant analysis of the questionnaire data, each type of pain was found to occupy a different region in the multidimensional space derived from the pain descriptions. Further statistical analysis of the data revealed that the differences among the constellations of words for the eight syndromes are statistically significant. Each type of pain, therefore, appears to be characterized by a distinctive constellation of verbal descriptors. On the basis of the discriminant analysis, the descriptor-set for each patient was classified by the computer program into one of the eight diagnostic categories. A correct classification was made in 77% of the cases. The McGill Pain Questionnaire thus appears to have potential value as a diagnostic technique.