Five questions predicted long-term, severe, back-related functional limitations: evidence from three large...

The objectives of the study were as follows: (1) to investigate whether the predictive validity of a previously developed back pain prediction rule could be improved; (2) to determine if the rule can be shortened without loss of predictive validity; (3) to compare the rule with the physician's judgment; (4) to assess, in a different population, its 2-year predictive validity; and (5) to evaluate the clinical applicability of the rule in a first-line care setting.

One thousand two hundred and sixty-two participants were enrolled in the study (participation: 91%) before a medical consultation for nonspecific back pain in a large emergency room and were followed up for 2 years (follow-up: 92.5%). The effects of adding new items and deleting any one of the original items were evaluated. The predictions by the rule and the physicians were compared with the 2-year actual functional limitations (measured with the Roland-Morris Disability Questionnaire).

Although the final prediction rule included only five items (feeling everything is an effort, trouble getting breath, hot/cold spells, numbness/tingling in parts of body, and pain in heart/chest), its predictive validity was greater than that of the original 17-item version and was superior to the physician's prediction. The rule was easily applied.

A five-item clinical prediction rule of long-term back-related functional limitations could help first-line care physicians to concentrate the clinical attention on patients at higher risk.