IMPORTANCE In 2011, the Centers for Medicare & Medicaid Services (CMS) approved intensive behavioral weight loss counseling for approximately 14 face-to-face, 10- to 15-minute sessions over 6 months for obese beneficiaries in primary care settings, when delivered by physicians and other CMS-defined primary care practitioners.   
 OBJECTIVE To conduct a systematic review of behavioral counseling for overweight and obese patients recruited from primary care, as delivered by primary care practitioners working alone or with trained interventionists (eg, medical assistants, registered dietitians), or by trained interventionists working independently.    EVIDENCE REVIEW We searched PubMed, CINAHL, and EMBASE for randomized controlled trials published between January 1980 and June 2014 that recruited overweight and obese patients from primary care; provided behavioral counseling (ie, diet, exercise, and behavioral therapy) for at least 3 months, with at least 6 months of postrandomization follow-up; included at least 15 participants per treatment group and objectively measured weights; and had a comparator, an intention-to-treat analysis, and attrition of less than 30% at 1 year or less than 40% at longer follow-up.   
 FINDINGS Review of 3304 abstracts yielded 12 trials, involving 3893 participants, that met inclusion-exclusion criteria and prespecified quality ratings. No studies were found in which primary care practitioners delivered counseling that followed the CMS guidelines. Mean 6-month weight changes from baseline in the intervention groups ranged from a loss of 0.3 kg to 6.6 kg. In the control group, mean change ranged from a gain of 0.9 kg to a loss of 2.0 kg. Weight loss in both groups generally declined with longer follow-up (12-24 months). Interventions that prescribed both reduced energy intake (eg, ≥ 500 kcal/d) and increased physical activity (eg, ≥150 minutes a week of walking), with traditional behavioral therapy, generally produced larger weight loss than interventions without all 3 specific components. In the former trials, more treatment sessions, delivered in person or by telephone by trained interventionists, were associated with greater mean weight loss and likelihood of patients losing 5% or more of baseline weight.   
 CONCLUSIONS AND RELEVANCE Intensive behavioral counseling can induce clinically meaningful weight loss, but there is little research on primary care practitioners providing such care. The present findings suggest that a range of trained interventionists, who deliver counseling in person or by telephone, could be considered for treating overweight or obesity in patients encountered in primary care settings.
True