National Clinical Trial Number NCT02286141.

Adolescents undergoing SG and RYGB experienced greater declines in BMI at 1- and 3-year follow-up time points, while laparoscopic adjustable gastric banding was significantly less effective for BMI reduction.

PurposeWe previously reported that yoga and intensive stretching had equivalent benefits for persons with chronic back pain and both were superior to self care. As part of this trial, we explored whether physical, cognitive, affective and physiological factors mediated the effects of yoga on patient outcomes. Methods228 persons with non-specific cLBP recruited from primary care and the general community were randomized to 12 weekly 75-minute classes of either yoga or intensive stretching, or to a self-care book. Back-related function (Roland-Morris Disability Scale), symptoms (0-10 score) and psychological mediators (fear avoidance, body awareness, self-efficacy, psychological distress, perceived stress, positive affect) were assessed at baseline and 6, 12, and 26 weeks later by blinded interviewers. Physical function was assessed at baseline and 12 weeks and saliva samples were collected for cortisol and DHEA analyses at baseline, 6 and 12 weeks. Open-ended questions were asked about benefits of yoga and stretching. Statistical analyses for mediators were conducted using the framework of Baron and Kenney. Results95% of participants responded to at least one follow-up interview. Of the potential mediators, only self-efficacy decreased significantly from baseline to 6 weeks for both interventions (p=0.0015 and 0.0129). Cortisol awakening response was marginally significant for yoga (p=0.08). For yoga, 18% of the effect was mediated by increased self-efficacy, 8% by cortisol awakening response, and 21% by any of the mediators. For exercise, 8% of stretching was mediated by self-efficacy.In response to open-ended questions about benefits, >20% of participants mentioned: learning new exercises (both groups); relaxation, increased awareness and the benefits of breathing (yoga), and benefits of regular practice (stretching). ConclusionWhile both interventions were superior to self-care, our mediator analysis showed these benefits were not well explained by our measured "mediators". Qualitative data suggest that yoga and stretching may exert comparable benefits through partially distinct mechanisms.

BackgroundDespite numerous options for treating back pain and the increasing healthcare resources devoted to this problem, the prevalence and impact of back pain-related disability has not improved. It is now recognized that psychosocial factors, as well as physical factors, are important predictors of poor outcomes for back pain. A promising new approach that matches treatments to the physical and psychosocial obstacles to recovery, the STarT Back risk stratification approach, improved patients’ physical function while reducing costs of care in the United Kingdom (UK). This trial evaluates implementation of this strategy in a United States (US) healthcare setting.MethodsSix large primary care clinics in an integrated healthcare system in Washington State were block-randomized, three to receive an intensive quality improvement intervention for back pain and three to serve as controls for secular trends. The intervention included 6 one-hour training sessions for physicians, 5 days of training for physical therapists, individualized and group coaching of clinicians, and integration of the STarT Back tool into the electronic health record. This prognostic tool uses 9 questions to categorize patients at low, medium or high risk of persistent disabling pain with recommendations about evidence-based treatment options appropriate for each subgroup. Patients at least 18 years of age, receiving primary care for non-specific low back pain, were invited to provide data 1–3 weeks after their primary care visit and follow-up data 2 months and 6 months (primary endpoint) later. The primary outcomes are back-related physical function and pain severity. Using an intention to treat approach, intervention effects on patient outcomes will be estimated by comparing mean changes at the 2 and 6 month follow-up between the pre- and post-implementation periods. The inclusion of control clinics permits adjustment for secular trends. Differences in change scores by intervention group and time period will be estimated using linear mixed models with random effects. Secondary outcomes include healthcare utilization and adherence to clinical guidelines.DiscussionThis trial will provide the first randomized trial evidence of the clinical effectiveness of implementing risk stratification with matched treatment options for low back pain in a United States health care delivery system.Trial registrationNCT02286141. Registered November 5, 2014.Electronic supplementary materialThe online version of this article (doi:10.1186/s12891-016-1219-0) contains supplementary material, which is available to authorized users.