Introduction: The spine red flag questions are a screening tool used to help identify patients with potential serious underlying spinal pathologies such as cauda equina syndrome, malignancy, fractures, or infections that would benefit from additional evaluation. This study quantifies the sensitivity and specificity of patient-reported and provider-reported red flags.
Methods: Five hundred patients were randomly selected from the complete sample of 4,313 patients that presented to a spine clinic between October 9, 2013 and June 30, 2014 who received primary care within the health system and who electronically completed a red flags questionnaire. Physician notes were manually reviewed to identify provider-reported red flags and the clinical diagnoses of patient within a one-year window around the index visit; these diagnoses were used as the gold standard for sensitivity, specificity, positive and negative predictive values calculations. Youden’s index was used to rank performance of the red flags.
Results: Twenty-six (5.2%) patients were excluded due to cancellations and lack of follow up visits. A history of cancer was the best performing red flag to screen for malignancy in both patient-reported [sensitivity: 0.75 (0.53-0.90), specificity: 0.79 (0.75-0.82)] and provider-reported [sensitivity: 0.92 (0.73-0.99), specificity: 0.78 (0.74-0.82)] settings. The best performing red flags for fractures were osteoporosis, steroid use, and significant trauma in combination together for patient-reported red flags [sensitivity: 0.59 (0.44-0.72), specificity: 0.65 (0.60-069)], and osteoporosis and trauma in combination together for provider-reported red flags [sensitivity: 0.88 (0.68-0.91), specificity: 0.79 (0.75-0.83)]. The prevalence of infection and cauda equina diagnoses in the sample population was insufficient to perform sensitivity and specificity analysis.
Conclusions: Patient-reported red flags have lower sensitivity and specificity than provider-reported red flags for identification of patients with serious spinal pathologies, suggesting that the use of provider-reported red flags is preferable. The results of the study help to identify the most useful red flags in clinical practice.
Patient Care: Acute lower back pain is a very common complaint amongst patients in developed countries. The research conducted will help to refine the red flag questions and direct clinical practice to better screen for serious pathologies underlying lower back pain.
Learning Objectives: By the conclusion of this session, participants should be able to: 1) Understand the use of red flags as a screening tool for serious underlying pathology causing lower back pain; 2) Identify the differences found in the study between patient-reported and provider-reported red flags; 3) Describe the limitations of the study; and (4) Provide possible future directions for research into red flags for lower back pain.