Final Research Plan

High Body Mass Index in Children and Adolescents: Interventions

June 30, 2022

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.

Figure 1 is an analytic framework that depicts four Key Questions to be addressed in the systematic review. The figure illustrates how primary care–relevant behavioral,  pharmacotherapy, or combined weight management interventions for children and adolescents with higher body mass index (BMI) (e.g., >85th percentile for age and sex) improve health outcomes (Key Question 1), and whether primary care–relevant behavioral,  pharmacotherapy, or combined weight management interventions for children and adolescents with higher BMI affect weight outcomes or cardiometabolic outcomes (Key Question 2). Additionally, the figure addresses whether primary care–relevant behavioral, pharmacotherapy, or combined weight management interventions for children and adolescents with higher BMI improve behavioral outcomes (Key Question 3), and if weight management interventions for children and adolescents may result in any harms (Key Question 4).

Abbreviations: BMI=body mass index; KQ=key question; MET=metabolic equivalent of task; MVPA=moderate-to-vigorous physical activity; PA=physical activity.

  1. Do primary care–relevant behavioral, pharmacotherapy, or combined weight management interventions for children and adolescents with higher body mass index (BMI) improve health outcomes?
  2. Do primary care–relevant behavioral, pharmacotherapy, or combined weight management interventions for children and adolescents with higher BMI affect weight outcomes or cardiometabolic outcomes?
  3. Do primary care–relevant behavioral, pharmacotherapy, or combined weight management interventions for children and adolescents with higher BMI improve behavioral outcomes?
  4. Are there harms associated with weight management interventions for children and adolescents?

Contextual questions will not be systematically reviewed and are not shown in the Analytic Framework.

  1. What is the prevalence of BMI assessment in children and adolescents in primary care practice? Does the prevalence of BMI assessment vary by age?
  2. How well does BMI predict adiposity and overall health? Does the predictive accuracy of BMI differ by race or ethnicity?
  3. Are there harms associated with diagnosing children and adolescents as being overweight or having obesity in the healthcare setting (e.g., harms associated with labeling)? Does the risk of harm differ across racial and ethnic groups or contribute to health inequities?
  4. What level of weight or relative weight decrease in children or adolescents with obesity reduces the likelihood of obesity in adulthood or health outcomes associated with obesity?
  5. What are the inequities in factors that support healthy eating and physical activity in youth (e.g., food insecurity, financial security, or neighborhood-level factors)?
  6. What are the inequities in access to or participation in weight management interventions?
  7. What are the harms of stigma and weight bias? What is the extent of weight bias in healthcare?
  8. Are there long-term harms of weight loss attempts during childhood or adolescence?

To the extent possible, we plan to describe the major intervention components and participant characteristics of the included studies. Key intervention components will include, for example: contact dose (number of sessions and duration of intervention), setting (general pediatric, medical specialty, or community), provider type, delivery format (in-person, phone, online, or print-based), use of group vs. individual sessions, presence of physical activity sessions, whether the intervention was tailored for a specific group (e.g., cultural, gender, or age [younger children or adolescents] group), and medication dose and duration (if applicable). Data on population characteristics will help us explore the degree to which the findings are broadly representative of the U.S. population, including a diversity of young persons across age; sex and gender identity; racial, ethnic, and cultural identity; socioeconomic status; baseline weight status; and geographic region. For efficacy key questions, we will evaluate the literature to determine if there are common components of efficacious intervention programs, and, to the extent possible, whether interventions tailored to specific groups tend to have larger effect sizes than those that are not tailored. We will highlight interventions that demonstrate effectiveness in traditionally stigmatized or underrepresented groups who have a higher prevalence of higher BMI, such as Black, Latino/Hispanic, and Native American/American Indian populations.

In addition to narrative and tabular synthesis, we will conduct meta-analyses if evidence is sufficient. We will evaluate statistical heterogeneity among studies using standard chi-squared tests and estimate the magnitude of heterogeneity using the I2 statistic. All analyses will be performed using Stata 16.1 (StataCorp, College Station, TX).

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.

  Include Exclude
Condition definition Studies identifying children with higher BMI, using measures such as BMI percentile (e.g., ≥85th percentile or ≥95th percentile), BMI z-score, percent overweight, or waist circumference  
Aim Studies with a primary aim of promoting weight reduction or stabilization, or maintenance of previous weight reduction or stabilization Healthy lifestyle counseling with no weight-related aim
Population Children and adolescents ages 2 to 18 years
  • Age- and sex-specific BMI ≥85th percentile or meets other similar criteria for higher BMI  
  • Previously had higher BMI and is now engaged in maintenance of weight loss or improved weight trajectory
  • Studies with an average age younger than 2 years or older than 18 years
  • Populations limited exclusively to youth who:
    • Have an eating disorder
    • Are pregnant or postpartum
    • Have medical conditions, such as diabetes (type 1 or 2), polycystic ovarian syndrome, hypothyroidism, Cushing’s syndrome, growth hormone deficiency, insulinoma, hypothalamic disorders (e.g., Froelich syndrome, Bardet-Biedl syndrome, Prader-Willi syndrome), asthma, or intellectual and developmental disabilities, or who are using medication associated with weight gain (e.g., antipsychotics)
    • Are in college (unless primarily includes persons age 18 years and younger)
Intervention
  • Weight management interventions include behavioral counseling, pharmacotherapy, and healthcare system–level approaches
  • Designed to promote weight reduction or stabilization, or maintenance of previous weight reduction or stabilization
  • May include the following, alone or in combination:
    • Behavioral-based interventions (e.g., behavior modification, cognitive behavioral therapy, mindfulness interventions, or health-behavior change counseling and coaching)
    • Pharmacologic interventions approved by the FDA for weight loss (i.e., orlistat and liraglutide)
    • Health system–level interventions (e.g., stepped care or collaborative care)
  • Must be either conducted in a primary care setting, feasible in “usual” primary care, or referable from primary care. Must at least involve the healthcare system in some way (may be limited to recruitment)
  • Primary prevention in children who are normal weight
  • Surgical interventions
  • Studies that include elements that cannot be implemented in the healthcare setting (e.g., changes in the physical/built environment or legislation)
  • Complementary and alternative medicine approaches (e.g., herbal supplements, acupuncture, Chinese medicine, or yoga)
  • Studies that provide all or most of participants’ food
  • Pharmacologic interventions not approved by the FDA (e.g., metformin)
Comparator Control groups with:
  • No intervention (e.g., wait-list control or usual care)
  • Minimal intervention (e.g., pamphlets or single annual session presenting information similar to what intervention groups receive through usual care in a primary care setting)
  • Attention control (e.g., similar format and intensity of intervention on a different content area)
  • Weight-neutral healthy lifestyle intervention
  • Placebo or no medication control for medication trials (both groups may include a behavioral weight management component)
Comparative effectiveness studies; the following components are too intensive to be considered usual care, so would be considered active comparators, including:
  • Personalized prescription for weight loss and exercise based on standardized dietary assessment
  • Homework, such as study-provided self-help workbooks with a weight loss focus
  • More than two annual intervention contacts (unless content not related to weight loss)
Outcomes Health outcomes:
  • Cardiovascular or weight-related morbidity or mortality
  • Quality of life or functioning
  • Depression

Intermediate outcomes:

  • Reduction or stabilization of weight or adiposity (required outcome). Acceptable measures include weight (kilograms or pounds), age- and sex-normative weight (BMI percentile, percent of the median BMI, percent of the 95th percentile BMI, or z-score for age and sex), relative weight (BMI or percent overweight), total adiposity (e.g., dual-energy x-ray absorptiometry, underwater weight, or comparable), other similar measures, or change in any of these measures
  • Weight maintenance after an intervention has ended
  • Cardiometabolic measures (included only when weight-related measures are also reported): insulin resistance/blood glucose/diabetes, blood pressure/hypertension, lipid levels/dyslipidemia, metabolic syndrome
  • Liver dysfunction/nonalcoholic fatty liver disease
  • Physical fitness capacity or performance

Behavioral Outcomes:

  • Dietary pattern score
  • Minutes per week of moderate-to-vigorous physical activity or MET-minutes per week
  • Percent meeting physical activity goals
  • Sedentary behavior or screen time

Harms:

  • Harms associated with labeling
  • Stigma or increased body image concerns or negative mental health effects
  • Negative impacts on provider-patient relationship (e.g., care avoidance or dissatisfaction with care)
  • Unhealthy weight management efforts (e.g., using laxatives or self-induced vomiting) or eating patterns (excessive fasting, overly restrictive eating, or binging)
  • Suppressed growth
  • Exercise-induced injury
  • Serious treatment-related harms at any time after initiation of intervention (i.e., death or medical issue requiring hospitalization or urgent medical treatment) or other treatment-related harms reported in trials meeting inclusion criteria for intermediate or health outcomes
  • Individual dietary intake components (e.g., fats, fiber, fruits, and vegetables)
  • Kilocalories/day
Timing of outcome assessment All KQs (except serious harms of pharmacotherapy): ≥6 months after baseline or beginning of weight loss phase

KQ 4 (serious harms of pharmacotherapy): No minimum followup. Serious harms are events resulting in death, hospitalization, or the need for urgent medical treatment

 
Setting
  • Primary care settings (e.g., pediatrics, family medicine, or school-based health clinics)
  • Other outpatient healthcare settings
  • Phone, mobile, or virtual settings (e.g., online intervention, if there is some connection to a health setting, such as recruitment from a healthcare setting)
  • Community or research settings, if there is some connection to a health setting (e.g., recruitment from a healthcare setting)
  • Community/university research laboratories or other nonmedical centers
  • College settings
  • Mental health clinics (unless recruitment is through primary care screening)
  • Correctional facilities
  • School classrooms
  • Worksites
  • Inpatient/residential facilities
  • Emergency departments
Study design All KQs: Randomized, controlled trials

KQ 4 (serious harms of pharmacotherapy): Large nonrandomized studies of interventions, defined as quantitative studies estimating the harms of an intervention that does not use randomization to allocate units to intervention groups. Such studies include those in which allocation occurs in the course of usual treatment decisions or according to patients’ choices

All other study designs
Country Studies that take place in countries categorized as “Very High” on the 2019 Human Development Index (as defined by the United Nations Development Programme; published 2020) Primary studies that are conducted in countries that are not categorized as “Very High” on the Human Development Index
Language English Languages other than English
Study quality Fair or good Poor, according to design-specific USPSTF criteria

Abbreviations: BMI=body mass index; FDA=U.S. Food and Drug Administration; KQ=key question; MET=metabolic equivalent of task; USPSTF=U.S. Preventive Services Task Force.

The draft Research Plan was posted on the U.S. Preventive Services Task Force (USPSTF) website from February 10, 2022 to March 9, 2022. Most comments received by the USPSTF made suggestions regarding which outcomes should be included. Based on public comments and key informant interviews, the USPSTF removed the outcomes of self-esteem/body satisfaction (due to cultural differences in beauty and body standards that make these data difficult to interpret at the study level), BMI z-score (due to lack of sensitivity to change at the highest BMI levels; however, the USPSTF will accept this outcome if it is the only weight outcome reported by a study), and sugar-sweetened beverage consumption (to maintain the focus on overall diet pattern). The USPSTF added outcomes reflecting sedentary behavior, including both sedentary time and screen time. Other changes that were made based on public comments include: adding text to clarify that a BMI exceeding the 85th percentile for age and sex serves as an acceptable definition of higher BMI; allowing weight-neutral healthy lifestyle counseling as a control group; and including studies with 6 to 11 months of followup.