Final Research Plan
Weight Loss to Prevent Obesity-Related Morbidity and Mortality in Adults: Behavioral Interventions
March 31, 2016
Recommendations made by the USPSTF are independent of the U.S. government. They should not be construed as an official position of the Agency for Healthcare Research and Quality or the U.S. Department of Health and Human Services.
The final Research Plan is used to guide a systematic review of the evidence by researchers at an Evidence-based Practice Center. The resulting Evidence Review forms the basis of the USPSTF Recommendation Statement on this topic.
The draft Research Plan was available for comment from December 10, 2015 until January 13, 2016 at 8:00 p.m., ET.
Abbreviation: HRQoL=health-related quality of life.
Figure 1 is the analytic framework that depicts the three Key Questions to be addressed in the systematic review. The figure illustrates how behavioral counseling or pharmacotherapy interventions for weight loss or weight loss maintenance may result in improved health outcomes, including obesity-related morbidity and mortality and health-related quality of life (KQ 1). Additionally, the figure illustrates how behavioral counseling or pharmacotherapy interventions for weight loss or weight loss maintenance may have an effect on intermediate outcomes (including weight loss and the incidence or prevalence of obesity-related conditions) (KQ 2). Further, the figure depicts whether behavioral counseling or pharmacotherapy interventions for weight loss or weight loss maintenance are associated with any adverse effects (KQ 3).
- Do primary care–relevant behavioral and/or pharmacotherapy weight loss and weight loss maintenance interventions lead to improved health outcomes among adults who are overweight or have obesity and are a candidate for weight loss interventions?
- Do primary care–relevant behavioral and/or pharmacotherapy weight loss and weight loss maintenance interventions lead to weight loss, weight loss maintenance, or a reduction in the incidence or prevalence of obesity-related conditions among adults who are overweight or have obesity and are a candidate for weight loss interventions?
- What are the adverse effects of primary care–relevant behavioral and/or pharmacotherapy weight loss and weight loss maintenance interventions in adults who are overweight or have obesity and are a candidate for weight loss interventions?
Contextual questions will not be systematically reviewed and are not shown in the Analytic Framework.
- Does the predictive value of body mass index (BMI) for future mortality and health risks differ by specific population subgroups (i.e., by race/ethnicity or older age)?
- Does primary care–feasible assessment of central adiposity increase the predictive value of BMI for future mortality and health risks?
- What health effects (i.e., mortality and incidence of cardiovascular disease, type 2 diabetes mellitus, or cancer) are associated with intentional weight loss, BMI reduction, or both?
The Research Approach identifies the study characteristics and criteria that the Evidence-based Practice Center will use to search for publications and to determine whether identified studies should be included or excluded from the Evidence Review. Criteria are overarching as well as specific to each of the key questions (KQs).
|Study aim||Weight loss or weight loss maintenance||
|Condition definition||Overweight or obesity, as defined by BMI or other weight-related measurements|
Studies limited to:
||Studies conducted in or recruited from settings not generalizable to primary care (e.g., worksites, university classrooms, institutional settings), in a population with pre-existing social ties (e.g., from the same worksite or church), or in a setting where the intervention could not be reproduced in primary care or within a broader health system|
|Interventions||Interventions focusing on weight loss/maintenance, including the following:
|Comparisons||For studies of behavioral interventions:
For studies of pharmacologic interventions:
|For studies of behavioral interventions:
For studies of pharmacologic interventions:
|Outcomes||KQ 1: Health outcomes:
KQ 2: Weight outcomes (required for inclusion) and incidence or prevalence of related conditions:
KQ 3: Adverse outcomes
KQ 2: Cardiometabolic measures (e.g., glucose levels, blood pressure, lipid levels)
|Timing of outcome assessment||KQs 1, 2: ≥12 months after start of intervention or baseline assessment (if the intervention start cannot be determined)
KQ 3: No minimum followup
|KQs 1, 2: <12 months after baseline|
|Countries||Studies conducted in economically developed countries, defined as member countries (2015) of the Organisation for Economic Co-Operation and Development (i.e., Australia, Austria, Belgium, Canada, Chile, Czech Republic, Denmark, Estonia, Finland, France, Germany, Greece, Hungary, Iceland, Ireland, Israel, Italy, Japan, Korea, Luxembourg, Mexico, Netherlands, New Zealand, Norway, Poland, Portugal, Slovak Republic, Slovenia, Spain, Sweden, Switzerland, Turkey, United Kingdom, United States)||
|Study designs||KQs 1, 2: Randomized or controlled clinical trials, including cluster randomized trials
|KQs 1, 2: Any observational studies, ecological studies, case reports, case series, or other noncomparative reviews or letters to the editor
KQ 3: Ecological studies, case-series, and case reports
|Study quality||Fair or good (according to design-specific USPSTF criteria)||Poor (according to design-specific USPSTF criteria)|
* Studies that focus on the effectiveness of primary care interventions for the primary prevention of cardiovascular disease or treatment of diabetes are included in separate reviews commissioned by the USPSTF (available at www.uspreventiveservicestaskforce.org).
The draft Research Plan was posted for public comment on the U.S. Preventive Services Task Force (USPSTF) Web site from December 10, 2015 to January 13, 2016. Several comments suggested including studies among women during the postpartum period; the USPSTF changed the Research Plan to include postpartum women. A number of comments suggested including interventions with surgical and nonsurgical devices for the treatment of obesity. The use of surgical and nonsurgical devices is considered part of disease management for persons with severe obesity or related comorbid conditions, and is outside the scope of this review. In addition, several comments advocated for the inclusion of studies among adults with comorbid conditions, particularly those with diabetes and sleep apnea. The USPSTF chose to maintain the exclusion of studies specifically among population subgroups for whom weight loss interventions are part of the treatment and management of clinical disease, as this is considered outside the scope of the USPSTF’s recommendations (i.e., tertiary care). Many comments pertained to insurance coverage, which is outside the scope of this review.