Pain assessment in context: a state of the science review of the McGill pain questionnaire 40 years on.

The McGill pain questionnaire (MPQ) and its later derivative the short form-MPQ have been used widely both in experimental and clinical pain studies. They have been of considerable importance in stimulating research into the perception of pain and now, with the publication of its latest variant, the short form-MPQ-2, it is appropriate to appraise their utility in the light of subsequent research into the nature of pain and the purpose of pain assessment. Following a description of the content and development of the questionnaires, issues of validity, reliability, and utility are addressed, not only in terms of the individual pain descriptors and the scales, but also in terms of methods of quantification. In addition, other methods of pain depiction are considered. In the second part of the review, advances in pain measurement and methodology, in the elucidation of pain mechanisms and pathways, in the psychology of pain, and in the nature of pain behavior are presented and their implications for pain assessment in general and the MPQ family of measures in particular will be addressed. It is suggested that pain assessment needs to be cast in its social context. We need to understand the influences on pain expression using a socio-communication model of pain that recognizes the function of pain and the importance of both innate pain responses and the effects of social learning. The review concludes with recommendations for future use of the MPQ and identifies a number of research challenges which lie ahead.