Over Half of Clinical Trials of Mobilization and Manipulation for Patients With Low Back Pain May Have Limited Real-World Applicability: A Systematic Review of 132 Clinical Trials

OBJECTIVE: To evaluate the existing body of trials assessing manual therapy for low back pain (LBP) to determine where it falls on the efficacyeffectiveness continuum. DESIGN: Methodology systematic review. LITERATURE SEARCH: PubMed, CINAHL (Cumulative Index to Nursing and Allied Health Literature), CENTRAL (Cochrane Central Register of Controlled Trials), and PEDro (Physiotherapy Evidence Database) were searched for trials published between January 1, 2000, and April 30, 2021. STUDY SELECTION CRITERIA: We included randomized clinical trials investigating joint mobilization and manipulation for adults with nonspecific LBP that were available in English. DATA SYNTHESIS: We used the Rating of Included Trials on the Efficacy-Effectiveness Spectrum (RITES) tool to score included trials across 4 domains: participant characteristics, trial setting, flexibility of intervention(s), and clinical relevance of experimental and comparison intervention(s). Proportions of trials with greater emphasis on efficacy or effectiveness were calculated for each domain. RESULTS: Of the 132 included trials, a greater proportion emphasized efficacy than effectiveness for domains participant characteristics (50% vs 38%), trial setting (71% vs 20%), and flexibility of intervention(s) (61% vs 25%). The domain clinical relevance of experimental and comparison intervention(s) had lower emphasis on efficacy (41% vs 50%). CONCLUSION: Most trials investigating manual therapy for LBP lack pragmatism across the RITES domains (ie, they emphasize efficacy). To improve real-world implementation, more research emphasizing effectiveness is needed. This could be accomplished by recruiting from more diverse participant pools, involving multiple centers that reflect common clinical practice settings, involving clinicians with a variety of backgrounds/experience, and allowing flexibility in how interventions are delivered.