Diagnostic utility of the McGill Pain Questionnaire and the Oswestry Disability Questionnaire for classification of low back pain syndromes.

Verbal pain description and assessment of functional limitations are key components in the clinical evaluation of patients with low back pain syndromes. Using the McGill Pain Questionnaire (MPQ) to quantify the pain experience and the Oswestry Disability Questionnaire (ODQ) to quantify functional disability, a study was undertaken to determine the efficiency with which the MPQ and ODQ were capable of enhancing the differential diagnosis of three broad categories of low back syndromes. Three discriminative models were employed. The combined discriminant model (MPQ/ODQ) yielded the highest accuracy, 0.90, and it was the only model with acceptable predictive power. The greatest utility of the discriminant models was found to be ruling out nonspecific low back pain and ruling in radiculopathy, with and without neurological deficits. Subjective pain and disability appear to have the potential for successfully differentiating broad categories of low back pain. Further studies need to be performed to assess the discriminant power of the MPQ and ODQ for specific diagnostic entities.