Henschke and colleagues present a large clinical survey drawn from a primary care practice that seeks to establish the prevalence and types of serious spinal disorders hidden within the herd of common back pain patients. As pure a measure of prevalence as possible was obtained by including only those patients presenting for their first consultation for the current episode of back pain, excluding patients with serious pathology diagnosed before referral and working within a system with a strong gate-keeper: patients are rarely able to skip the primary care provider and see the spine specialist directly. The authors then assessed 25 ‘red flags’ in the intake history that might guide physicians to more extensive evaluations required to diagnose serious underlying conditions.

The authors assembled a group of physicians from their region and screened 3184 consecutive back pain patients over a 20-month period. Of these patients, 1172 had acute low back pain with no known serious condition. Interestingly, 11 patients from the original group were identified as having serious conditions in initial screening and were excluded from the study.

A review of the red-flag questions showed that a few had value: they led the physician to gather more information and discover …