Sequenced Care Pathway vs Pain Navigator Pathway for Veterans With Low Back Pain: The AIM-Back Cluster Randomized Clinical Trial.

Importance: Low back pain (LBP) is a leading cause of disability, and there is limited evidence from clinical practice to support the effectiveness of alternative care models. Objective: To compare a sequenced care pathway (SCP) with a pain navigator pathway (PNP) for patients with LBP. Design, Setting, and Participants: In this embedded cluster randomized clinical trial, 19 primary care clinics in the Veterans Health Administration were randomized to deliver 1 of 2 multimodal guideline-supported care pathways, with primary outcomes assessed in their electronic health records (EHRs) at 3 months. Between February 8, 2021 (first enrolled), and January 31, 2024 (last enrolled), 1817 participants were referred by primary care clinicians and attended an initial AIM-Back trial visit. A subset of 799 participants consented to complete additional questionnaires for secondary analyses (March 8, 2021 [first survey collected], to January 10, 2025 [final secondary outcome collected by survey]). Interventions: The SCP included pain education and modulation, physical activity coaching, risk stratification, and psychologically informed physical therapy. The PNP included shared decision-making and facilitated referrals to nondrug treatments. Main Outcomes and Measures: Pain interference and physical function were coprimary outcomes, assessed with the Patient-Reported Outcomes Measurement Information Systems 4-item Short Forms (PROMIS-SF; potential score range for pain interference, 41.6-75.6, where lower scores indicated less interference with daily activities due to pain; and potential score range for physical function, 22.5-57.0, where higher scores indicated higher physical functioning during daily activities). Secondary EHR outcomes included sleep disturbance and National Institutes of Health pain intensity, and survey outcomes included the coprimary outcomes and additional measures of pain, function, and quality of life. Analysis was performed in the intent-to-treat population. Results: There were 1817 enrolled participants (SCP, 811; PNP, 1006; mean [SD] age, 53.0 [15.7] years; 1597 men [87.9%]). At 3 months, 461 of 811 patients (56.8%) in the SCP group and 537 of 1006 (53.4%) in the PNP group had analyzable primary outcomes. The estimated baseline mean PROMIS-SF score was 63.2 points (97.5% CI, 62.7-63.6 points) for pain interference and 37.1 points (97.5% CI, 36.7-37.4 points) for physical function. The 3-month mean PROMIS-SF score for pain interference was 60.5 points (97.5% CI, 59.7-61.3 points) in the SCP group and 61.1 points (97.5% CI, 60.4-61.8 points) in the PNP group. The 3-month mean PROMIS-SF score for physical function was 39.1 points (97.5% CI, 38.4-39.7 points) in the SCP group and 38.5 points (97.5% CI, 37.8-39.1 points) in the PNP group. There was no SCP superiority, with estimated 3-month differences of -0.6 points (97.5% CI, -1.6 to 0.4 points) for pain interference and 0.6 points (97.5% CI, -0.3 to 1.5 points) for physical function. There were no pathway differences in secondary outcomes. Conclusion and Relevance: In this cluster randomized trial, the SCP was not superior for the primary outcomes of pain interference and physical function. Future research should consider designs that optimize pathway adherence, assess the effectiveness in other settings, and investigate patient-level factors indicative of a favorable response to the SCP or PNP. Trial Registration: ClinicalTrials.gov Identifier: NCT04411420.