Measuring functional outcomes in persons with back pain - A review of back-specific questionnaires

It is now widely recognized that patients' perspectives are essential in making medical decisions and judging the results of treatment.(17) Patient-based outcome measures are usually classified as generic or disease specific.(32) Both types of instruments have been used in back pain research during the past two decades. Generic measures include global ratings of health status, as well as multidimensional measures of health-related quality of life (HRQOL), such as the Sickness Impact Profile (SIP),(3) SF-36 Health Survey,(48) Nottingham Health Profile (NHP),(19) or shorter instruments.(20,49) Generic measures are applicable to patients across different types of conditions. The hallmark of a disease-specific measure is the attribution of symptoms and functional limitations to a specific disease or condition. Unlike items in a generic measure, items in a disease-specific measure assess only those aspects of health that tend to be affected by the disease. The goal is to achieve high relevance and responsiveness of the scales without undue burden to the patient.(32) This review is limited to validated functional questionnaires that were designed by selecting items relevant to back pain. Generic measures of HRQOL and pain measures are discussed elsewhere in this issue of Spine.(45,50) It should be noted that some general pain and disability instruments have been tested in patients with low back pain.(13,25,30,41,43) Furthermore, a large number of other questionnaires and rating schemes have been used to evaluate outcomes in patients with back pain.(22,52) However, most of these questionnaires have been developed ad hoc for a single study, their psychometric properties have not been reported, and comparisons with other scales have not been made.