Evidence Base Update on Behavioral Treatments for Overweight and Obesity in Children and Adolescents

ABSTRACT

Objective

This review provides an update to a previous Evidence Base Update addressing behavioral treatments for overweight and obesity in children and adolescents.

Method

Articles were identified through a systematic search of the biomedical literature in PubMed/MEDLINE (1946-), Elsevier EMBASE (1947-), SCOPUS (1823-), Clarivate Web of Science Core Collection (WOS, 1900-), PsycINFO (1800-), The Cochrane Library and Clinicaltrials.gov published between June 2014 and August 2022.

Results

Family-based treatment (FBT) remains a well-established treatment for overweight and obesity in children and is now well-established in adolescents and toddlers. Parent-only behavioral treatment remains well-established in children and is now well-established among adolescents and children. Possibly effective treatments continue to include FBT-parent only for adolescents, and behavioral weight loss (BWL) with a family component for adolescents, children, and toddlers. Several variations of FBT and BWL can now be considered possibly effective including FBT+motivational interviewing, FBT+social facilitation maintenance, group-based FBT, low-dose FBT, BWL+stress management, and camp-based BWL. Cognitive behavioral treatment (CBT) for adolescents also met criteria for possibly effective treatments. Current research has also established that behavioral treatments can be effectively delivered in alternative settings (e.g. primary care) and through alternative mediums (e.g. telehealth).

Conclusions

Research continues to support the use of multicomponent lifestyle interventions in accordance with recent recommendations from the American Academy of Pediatrics, the American Psychological Association, and the United State Preventative Services Task Force. However, more work is needed to ensure appropriate access for children with comorbid medical and psychiatric disorders and children from socially, politically, and economically marginalized groups.

Introduction

Rates of overweight and obesity remain high among youth. Almost 20% of children and adolescents in the United States aged 2–19 years have obesity, 6.1% have severe obesity, and another 16.1% have overweight (Fryar et al., 2020). Despite prevention and treatment efforts, rates have not declined in recent years (Ogden et al., 2020). Obesity is strongly associated with increased risk of cardiovascular disease in both adults and children (Freedman et al., 1999; Koliaki et al., 2019) as well as metabolic syndrome (Engin, 2017). Obesity in children is also associated with worse mental health and psychosocial outcomes including disordered eating and low self-esteem (Goldschmidt et al., 2008; Halfon et al., 2013; Strauss, 2000).

In addition to increasing risk for specific disorders, obesity is associated with increased mortality (D’Souza et al., 2018), disability (Ferraro et al., 2002), and worse quality of life (Kushner & Foster, 2000) contributing to billions of dollars in direct medical costs and lost productivity in the U.S. (Hammond et al., 2010) and globally (Okunogbe et al., 2021). Evidence also shows that childhood obesity is strongly predictive of obesity in adulthood such that 22% to 90% of youth with overweight or obesity will retain that status in adulthood (Singh et al., 2008). As such, obesity presents an important public health challenge and identifying effective treatments for overweight and obesity in youth is of utmost importance. The present review provides an update to the 2015 Evidence Base Update published on the same topic (Altman & Wilfley, 2015).

Methods

Search Strategy

Treatment studies addressed in this review were identified with the assistance of a medical librarian. A systematic search of the biomedical literature in PubMed/MEDLINE (1946-), Elsevier EMBASE (1947-), SCOPUS (1823-), Clarivate Web of Science Core Collection (WOS, 1900-), PsycINFO (1800-), the Cochrane Library and Clinicaltrials.gov. The controlled vocabulary of each database and plain language was used in creating a search strategy for the terms “Overweight,” “Obesity,” “Pediatric Obesity,” “Behavior Therapy,” “Cognitive Behavioral Therapy,” “Precision Medicine,” and “Child and Adolescent.” All results were exported to EndNote. The medical librarian used the duplicate finder in EndNote and 2998 duplicates were assumed to be accurately identified and removed for a total of 3782 unique citations. The final search results were limited from June 2014- to August 2022. The reference sections of relevant articles were also reviewed to identify any additional studies for inclusion in this review. Finally, recent reviews and meta-analyses on this topic were examined to ensure that no pertinent studies were missed.

Treatment Designations

For purposes of this review, treatments are designated as well established if the treatment efficacy has been shown to be (a) superior to a psychological placebo or wait-list control or (b) equal to a well-established treatment in at least two research settings by two independent researchers (Southam-Gerow & Prinstein, 2014). A treatment is considered probably efficacious if it has been shown to be (a) superior to a waitlist control group in at least two randomized clinical trials (RCTs), or (b) meets criteria to be a well-established treatment but has not been tested by two or more research teams. Treatments are considered possibly efficacious if they have demonstrated efficacy over the control group in at least one RCT, or two or more clinical trials. Treatments that have not been tested in an RCT or with at least two clinical trials but have some support are considered experimental, and treatments found inferior to other treatment groups or waitlist control groups are considered of questionable efficacy.

Studies were included in this review if they (a) tested interventions or treatments for childhood obesity; (b) were conducted in a defined population of toddlers (ages 2–5), children (ages 6–12), and/or adolescents (ages 13–18) with overweight or obesity; (c) provided description of the intervention; (d) included weight change as an outcome measure; and (e) used clearly defined study inclusion and exclusion criteria. Per the previous evidence base update (Altman & Wilfley, 2015), the present review focuses on psychological treatments for childhood and adolescent overweight and obesity.

Treatment Outcome Measurements

For a detailed discussion of treatment outcome measures, see Altman and Wilfley (2015). As with the original evidence base update, the majority of articles reviewed used Body Mass Index (BMI) or derivations of BMI as a primary outcome measure. The most common outcome measure was BMIz or BMI-SDS which refer to the distribution of BMI scores for a child’s age and sex (Cole et al., 2005). Other common measures included BMI percentile, percent overweight (percent above median BMI for age and sex) and waist circumference as well as direct measures of adiposity (Paluch et al., 2007). Research suggests that in youth, particularly younger children who are still growing, relatively small changes in weight (−7.55 to +3.90 kg) can be sufficient to achieve non-overweight status over one year. For example, an 8-year-old girl whose BMI is in the 97^th percentile would need to lose 1.8 kg. However, a 12-year-old girl with the same BMI percentile but who would be expected to grow less, would need to lose 7.6 kg (Goldschmidt et al., 2013). Reductions in BMI percentile between 5–10% are considered clinically significant and may be recommended for children with more severe obesity (BMI ≥99^th percentile) (Ford et al., 2010).

While the present evidence base update focuses on weight change as the primary measure of treatment efficacy in order to compare across highly heterogeneous studies, many studies also reported other health outcomes (e.g., cardiometabolic changes), as well as psychosocial outcomes (e.g., quality of life, self-esteem, mental health), family metrics (e.g., parent/caregiver weight change), and process metrics (e.g., family retention, patient satisfaction). These examples of non-weight outcome measures have been identified as increasingly important to providers, patients, payers, and policy makers (Wilfley, Staiano, et al., 2017).

Treatment Components & Types

Broadly, behavioral treatments for pediatric obesity involve three components: 1) changes to diet and nutrition typically aimed at improving diet quality and reducing overall caloric intake, 2) increases in physical activity and decreases in sedentary behaviors, and 3) behavioral strategies aimed at facilitating the first two components (e.g., self-monitoring, stimulus control) (Wilfley et al., 2018). Treatments may also promote positive parenting skills (e.g., praise, healthy communication and modeling) or target broader social networks (e.g., encourage peer support) in order to encourage behavior change (Hayes et al., 2018). Previous research has found that multicomponent treatments for pediatric obesity are superior to single component treatments (e.g., Ho et al., 2012; Wilfley et al., 2007). Since the previous evidence base update, several governmental and professional organizations have released guidelines or position statements recommending multicomponent behavioral treatment for children and adolescents with overweight and obesity (Table 1). Themes across these recommendations are that children 6 years or older with overweight or obesity should be referred to comprehensive, intensive behavioral treatment that is either family-based or includes a family component and consists of at least 26 contact hours (American Psychological Association, 2020; Grossman et al., 2017; Hampl et al., 2023; Kirk et al., 2022). The Academy of Nutrition and Dietetics also recommends that children receive culturally appropriate treatments that are tailored to their individual needs.

Table 1. Summary of recent evidence updates and recommendations.

Organization, Year	Title	Recommendations
American Academy of Pediatrics, 2023	Clinical Practice Guideline for the Evaluation and Treatment of Children and Adolescents with Obesity	Pediatricians and other PHCPs should provide or refer children 6 y and older (Grade B) and may provide or refer children 2 through 5 y of age (Grade C) with overweight (BMI ≥85th percentile to <95th percentile) and obesity (BMI ≥95th percentile) to intensive health behavior and lifestyle treatment. Health behavior and lifestyle treatment is more effective with greater contact hours; the most effective treatment includes 26 or more hours of face-to-face, family-based, multicomponent treatment over a 3- to 12-mo period.
Academy of Nutrition and Dietetics, 2022	Treatment of Pediatric Overweight and Obesity: Position of the Academy of Nutrition and Dietetics Based on an Umbrella Review of Systematic Reviews	It is the position of the Academy of Nutrition and Dietetics that children and adolescents with overweight or obesity should receive multi-component, culturally appropriate interventions with family involvement and nutrition counseling from an RDN. RDNs should use appropriate screening and assessment methods that address weight and mental health status; use inclusive language; and work within their scope of practice to provide nutrition assessment and tailored interventions that leverage new technology to improve health outcomes.
American Psychological Association, 2020	Summary of the Clinical Practice Guideline for Multicomponent Behavioral Treatment of Obesity and Overweight in Children and Adolescents	For child and adolescent patients aged 2 to 18 years with obesity or overweight, the [Guideline Development Panel] strongly recommends the provision of family-based multicomponent behavioral interventions, with a minimum of 26 contact hours, initiated at the earliest age possible.
United States Preventative Services Task Force, 2017	Obesity in Children and Adolescents: Screening	The USPSTF recommends that clinicians screen for obesity in children and adolescents 6 years and older and offer or refer them to comprehensive, intensive behavioral interventions to promote improvements in weight status. The USPSTF found that comprehensive, intensive behavioral interventions with a total of 26 contact hours or more over a period of 2 to 12 months resulted in weight loss.

Family-Based Treatment Vs. Multicomponent Behavioral Weight Loss with a Family Component

Following Altman and Wilfley (2015), efforts were made to distinguish between family-based treatment (FBT) and behavioral weight loss (BWL) with a family component. FBT, which is a specific type of treatment, asks parents to not only facilitate their child’s behavior change, but to set their own behavior change goals and actively participate in treatment alongside their child. FBT also utilizes an explicitly socioenvironmental approach targeting family relationships, the home food environment, and broader social networks (Epstein et al., 2007). Other treatments may encourage parents to attend sessions or assist their children to make behavior changes but not set goals of their own. For purposes of the present evidence base update, treatments that did not explicitly state that parents actively participated in treatment were considered BWL with a family component. See Table 2 for descriptions of main treatment types.

Table 2. Major treatment types.

Treatment	Definition
Family-Based Behavioral Treatment (FBT)	Parents facilitate both their children’s and their own behavior change goals and actively participate alongside their child in treatment (Epstein et al., 2007)
Parent-Only Behavioral Treatment (PBT)	Parents facilitate their children’s and their own behavior change goals, but the child does not participate directly in treatment (e.g., Boutelle et al., 2017)
Behavioral Weight Loss (BWL)	Any treatments which incorporated behavioral components but did not specify an established treatment modality (e.g., FBT)
[Treatment] with Family Component	Parents facilitate their children’s behavior change goals, but not necessarily their own. Includes treatments where children and parents are treated together and where children and parents may receive treatment during separate, sometimes co-occurring sessions.
[Treatment] with Parent Component	Parents facilitate their children’s behavior change goals, but not necessarily their own. The child does not participate directly in treatment.
Motivational Interviewing (MI)	Person-centered, conversational approaches designed to overcome ambivalence surrounding treatment and motivate behavior change.
Mindfulness (MF)	Approaches which center non-judgmental attention paid to the present in order to promote conscious eating through emotion regulation.
Mindful Eating (ME)	Approaches which center non-judgmental attitudes toward food and attention to hunger, satiety, and sensation cues to facilitate healthy eating patterns. Expands on MF.

Results

We identified 118 studies through the aforementioned literature search across seven theoretical treatment frameworks (Table 3). Few studies examined the effectiveness of a treatment itself; rather, studies typically examined the effectiveness of novel treatment deliveries (e.g., telehealth) or adjunctive programs (e.g., peer support through social media). For the sake of space, RCTs trump non-RCTs: if RCTs demonstrate treatment efficacy, we do not present the findings of non-RCTs.

Table 3. Summary of treatments by level of support.

	Adolescents	Adolescents & Children	Children	Children & Toddlers	Toddlers	Adolescents, Children & Toddlers
Level 1: Well-Established Treatments	FBT	FBT; PBT	FBT^a; PBT^a		FBT
Level 2: Probably Effective Treatments
Level 3: Possibly Effective Treatments	FBT at home; FBT + MI; FBT-Parent-only ^a; Community-based BWL; CBT; CBT in integrated care; MI+Parent component	FBT+SFM; BWL+Family ^a; BWL+Parent Component; BWL+Stress Management	FBT-Group; FBT-Web; FBT-Parent-Only; Low-dose FBT; Low-dose FBT + MI; FBT-educational board game; FBT + Peer; BWL+Family ^a; Camp-based BWL		BWL+Family^a
Level 4: Experimental Treatments	BWL; Inpatient CBT; CBT+LI; Mindful Eating	FBT+DBT; BWL; Low-Dose BWL+Family; BWL+Exercise (males only); camp-based BWL; Mindfulness + Nutritional Counseling	FBT+Exercise; BWL; Group BWL+Family; BWL+Parent-Component; home-based BWL; CBT-Parent only; CBT-PEAT (males only)			FBT-Group; BWL
Level 5: Treatments of Questionable Efficacy	BWL+Peer Support; School-based BWL; MI; Mindfulness	Smartphone/App-based BWL	Parents-only BWL; BWL via newsletter; Smartphone/App-based BWL; CBT; CBT+Parent component; Low-intensity MI; text-based MI	BWL+MI	MI
a: The same as Altman and Wilfley (2015)

Note: BWL = Behavioral Weight Loss; CBT = Cognitive Behavioral Treatment; FBT = Family-based Treatment; LI = Lifestyle Intervention; MI = Motivational Interviewing; PBT = Parent-only Behavioral Treatment; PEAT = Peer Enhanced Adventure Therapy; SFM = Social Facilitation Maintenance.

Family-Based Behavioral Treatment (FBT)

FBT remains a Well-Established Treatment for children (Altman & Wilfley, 2015). Thirty-two included studies examined the effectiveness of treatments based on FBT. Of these studies, 20 were RCTs, of which 17 were found to be effective in treating adolescents (3), adolescents and children (2), children (10), and toddlers (2), indicating that FBT is a Well-Established Treatment across age groups.

Since FBT’s establishment as the gold-standard for the treatment of childhood obesity, recent studies have tested the effectiveness of additions of other methods for or locations of treatment delivery. Only one RCT has been published for each, and they are therefore considered Possibly Efficacious Treatments. Among adolescents, these include home treatment (as compared to office treatment; Naar et al., 2019) and adjunctive MI (Jacques-Tiura et al., 2019), as well as adjunctive SFM for adolescents and children (Skjåkødegård et al., 2022). For children, these include group-based (Kokkvoll et al., 2020), web-based (Varagiannis et al., 2021), and parent-only (Yackobovitch-Gavan et al., 2018) deliveries, as well as low dose (Looney & Raynor, 2014), low-dose with motivational interviewing (Taylor et al., 2015), educational board game (Sen et al., 2018), and peer engagement methods (Saelens et al., 2017).

Experimental Treatments include exercise as an adjunctive treatment for children (Labayen et al., 2020), group-based delivery for toddlers, children, and adolescents (Tripicchio et al., 2018), and adjunctive dialectical behavioral treatment (DBT) among adolescents and children (Boutelle et al., 2018).

Parent-Only Behavioral Treatment (PBT)

PBT remains a Well-Established Treatment for children (Altman & Wilfley, 2015). This review additionally found PBT to be a Well-Established Treatment for children and adolescents based on two studies comparing its effectiveness to FBT (Bohlin et al., 2017; Boutelle et al., 2017).

Behavioral Weight Loss (BWL)

Fifty-three included studies examined the effectiveness of BWL. Of these studies, 22 were RCTs, of which 12 were found effective in adolescents (1), adolescents and children (5), children (5), and children and toddlers (1).

Sixteen studies evaluated BWL alone. Of these, only two were RCTs, one conducted among adolescents (Hoying et al., 2016) and the other among children (Hopkins et al., 2019), neither of which evidenced efficacy. One RCT taking a “stepped down” approach among children found a reduction in BMI among boys but not girls (Norman et al., 2016). Among non-RCTs, one found BWL effective in toddlers, children, and adolescents (Bayoumi et al., 2019), one found BWL effective in children (Kozioł-Kozakowska et al., 2019), and eight found BWL effective in adolescents and children (Hvidt et al., 2014; Martos-Moreno et al., 2021; Matusik et al., 2015; Nemet et al., 2014; Nobles et al., 2016; Reinehr et al., 2018; Rijks et al., 2015; Siegrist et al., 2021). Additionally, 2 non-RCTs found BWL effective in adolescents (Lee & Kim, 2015; Masquio et al., 2016), while 2 more did not (Luca et al., 2015; Melnyk et al., 2015). BWL is therefore considered an Experimental Treatment.

BWL with Family Component

The previous evidence base update found BWL with a family component to be possibly efficacious in adolescents and children, children, and toddlers (Altman & Wilfley, 2015). Three RCTs found evidence for BWL with a family component among adolescents and children (Nicol et al., 2019; Parra-Medina et al., 2015; van der Baan-Slootweg et al., 2014), and one more in children only (Wylie-Rosett et al., 2018). Additionally, a community-based BWL with family component intervention was effective in adolescents (Patsopoulou et al., 2017). An additional RCT found that BMI-SDS decreased in both the intervention and control groups to the same extent (Willeboordse et al., 2016). Group-based BWL with family component is Possibly Efficacious as it was found to be effective in children in a pilot RCT among American Indians (Sauder et al., 2018) and quasi-experimental study in Sweden (Hagman et al., 2020). A low-dose version of BWL with family component was found to reduce BMI in adolescents and children among adherents and may be considered an Experimental Treatment.

BWL with Parent Component

One RCT found BWL with a parent component to be effective among children and adolescents (Arlinghaus et al., 2021), suggesting that it is Possibly Efficacious for this group. Two non-RCTs examining BWL with parent components among children were also conducted. One found BWL with parent component to be effective (Jortberg et al., 2016) while the other did not (Arenaza et al., 2020), suggesting that BWL with parent component is experimental in children. Two RCTs studying BWL delivered to parents only, in person (Spence et al., 2023) and via newsletter (Kim et al., 2016), were not found to be effective in children. Parents-only BWL is therefore considered to be a Treatment of Questionable Efficacy in children.

BWL with Other Components

BWL with stress management was found to be effective in an RCT among adolescents and children (Emmanouil et al., 2018), and may be considered Possibly Efficacious. BWL with an exercise component was found effective in male, but not female, children and adolescents in a quasi-experimental trial in South Korea (Woo et al., 2022).

BWL with MI was not found to be effective in an RCT among children and toddlers (Taveras et al., 2017), nor was BWL with peer support effective in an RCT among adolescents (Kulik et al., 2015). BWL delivered via newsletter was also not supported in an RCT among children (Kim et al., 2016).

BWL in Different Settings

BWL delivered through a camp setting was found to be effective among children in 2 RCTs (Benestad et al., 2017; Papageorgiou et al., 2022), and is therefore considered to be Possibly Efficacious. Among adolescents and children, however, it is considered Experimental as it has only demonstrated success in 2 non-RCTs (Marx et al., 2015; Vlaev et al., 2021). Further, a cross-sectional study of a home-based BWL intervention was found to be effective among children (Spurrier et al., 2016).

BWL delivered in a school setting was not found effective in an RCT among adolescents (Pbert et al., 2016), nor was BWL delivered in an inpatient setting effective among children in an RCT (Warschburger et al., 2016). Further, RCTs of smartphone-based BWL demonstrated effectiveness among neither children (Salahshoornezhad et al., 2022) nor adolescents and children (Mameli et al., 2018).

Cognitive Behavioral Treatment (CBT)

Eleven studies examined the efficacy of cognitive behavioral treatment (CBT). Of these, 4 were RCTs. CBT alone (Miri et al., 2019) and CBT in integrated care (Fleischman et al., 2016) were found to be effective among adolescents, while CBT alone (Baños et al., 2019) and CBT with a parent component (Fernández-Ruiz et al., 2021) were not effective among children. Therefore, CBT is Possibly Efficacious in treating obesity in adolescents but of Questionable Efficacy among children.

Two non-RCTs examined the use of CBT delivered to parents only, finding it to be effective in children (Bennett et al., 2018; Karbasi Amel et al., 2018). Among adolescents, CBT in an inpatient setting (Doughty et al., 2015) and with an adjunctive lifestyle intervention (Çağlayan & Demirpençe Seçinti, 2020) were found to be effective in non-RCTs. In another study of CBT with supervised aerobic exercise (CBT-EXER) versus CBT with a peer-enhanced adventure therapy (CBT-PEAT), CBT-PEAT was more effective in boys than CBT-EXER, while both were equally effective in girls (Rancourt et al., 2018). CBT with adjunctive treatments are therefore experimental in children and in adolescents.

Motivational Interviewing (MI)

Eleven studies examined the efficacy of motivational interviewing (MI). Of these, 9 were RCTs. MI alone was not effective in 2 RCTs in adolescents (Christie et al., 2017; Segalla et al., 2020). In a SMART trial among African American adolescents, the effects of MI on weight were moderated by executive function rather than whether the intervention occurred in the home or office; however, the home-based intervention led to greater retention (Naar-King et al., 2016). An RCT of a low intensity MI intervention in children was also not effective (Stovitz et al., 2014).

One RCT found MI with a parent component to be effective in adolescents (Pakpour et al., 2015) while another did not (Bean et al., 2018). MI with a parent component delivered via text was not effective in an RCT in children (S. Armstrong et al., 2018). Moreover, MI with caregivers was less effective than an FBT-based intervention in an RCT among Appalachian toddlers in both the short- (Stark et al., 2018) and long-term (Stark et al., 2019).

Mindfulness (MF)

Mindfulness (MF) was examined in 2 non-RCTs. Mindfulness was not found to be effective among adolescents (Cotter et al., 2020), while it was found effective in conjunction with nutrition counseling among adolescents and children (López-Alarcón et al., 2020).

Mindful Eating (ME)

Mindful eating (ME) was examined in adolescents in 2 studies, 1 of which was an RCT. ME was not found to be effective among adolescents in the RCT (Hinton et al., 2018), although it was found to be effective in a pilot randomized feasibility study (Daly et al., 2016).

Treatment Settings

As with the previous evidence base update, most studies were conducted in clinical research or outpatient settings. However, alternative treatment settings are an important area of innovation. Five included studies took place in primary care settings (Crespo et al., 2018; Looney & Raynor, 2014; Parra-Medina et al., 2015; Quattrin et al., 2014; Riggs et al., 2014) and of those, four demonstrated efficacy including a high quality RCT (Quattrin et al., 2014). Several studies also delivered care in school or community settings but outcomes in these settings were more mixed. Studies effective at promoting weight loss typically involved both children or adolescents and a parent or caregiver (e.g., Gallo et al., 2020; Sauder et al., 2018) and included content aimed at changing the home food environment. Several treatments delivered in day or sleep-away camps also appear promising. An RCT of FBT implemented through a six-week day camp led to weight loss that was maintained at one year (Larsen et al., 2016). While more work is needed in this area, recent research suggests that evidence-based treatments such as FBT can be successfully implemented in primary care, community, or camp settings.

Medium of Delivery

A majority of reviewed treatments were delivered through face-to-face visits, but several studies explored alternative delivery mechanisms including mobile app, text message, telephone, and telehealth. A randomized comparison of FBT delivered through telehealth and telephone to children living in a rural area found that both delivery methods had good feasibility and acceptability and lower attrition compared to previous studies in similar populations (Davis et al., 2016). Similarly, a pilot study examining BWL delivered through adaptive text-messages over six months paired with one hour of in-person motivational interviewing for adolescents was found to be acceptable and produced promising preliminary weight loss (Jensen et al., 2019). Conversely, a study of daily motivational interviewing-based texts directed at parents of children with obesity for three months did not produce better weight loss results than standard care (S. Armstrong et al., 2018) although it did improve retention. Text-based treatments varied considerably with respect to content and dose, suggesting that, while these methods are promising and may ultimately reduce treatment costs and increase reach, more work is needed to clarify effective treatment dose and necessary behavioral targets.

Length and Dose

Treatment length and dose of reviewed studies varied considerably. Some treatments were relatively brief, consisting of as few as six direct contact hours over six weeks (e.g., Cotter et al., 2020). The longest treatment was five years in length and of variable dose (Danielsson et al., 2016). A majority of studies were between four months and one year in length and consisted of about 15–30 direct contact hours (e.g., Janicke et al., 2019; Kahhan et al., 2021) although some treatments involved over 100 hours of direct contact (e.g., Larsen et al., 2016). Of note, one study compared 12 weeks of FBT to 24 weeks of FBT (18 hours vs. 36 hours) and found the higher dose version of the treatment to be superior (Dreyer Gillette et al., 2014). This is in line with current recommendations from the AAP and the USPSTF that behavioral treatment for pediatric obesity consist of 26 contact hours or more.

Attrition

Rates of attrition also varied highly among studies. Some smaller studies managed to retain their entire sample (e.g., Amel et al., 2018; Fennig et al., 2015) while other studies saw attrition in excess of 50% (Bennett et al., 2018; Hagman et al., 2020). Studies with higher attrition tended to be in primary care or community settings.

Special Populations

Several studies examined the effects of behavioral treatments in specific, medically defined populations. These studies examined adolescents and children with autism spectrum disorders (Matheson et al., 2019), ADHD (Karbasi Amel et al., 2018), asthma (Willeboordse et al., 2016) metabolic syndrome (Masquio et al., 2016), isolated subclinical hypothyroidism (Matusik et al., 2015), and treatment with antipsychotics (Nicol et al., 2019).

Some US-based studies examined the effects of behavioral treatments specifically among socially, economically, and politically marginalized groups. These included African-American/Black children and adolescents (e.g., Jacques-Tiura et al., 2019; Naar et al., 2019), Hispanic/Latino/a children and adolescents (e.g., Crespo et al., 2018; Gallo et al., 2020; Parra-Medina et al., 2015), American Indian children (Sauder et al., 2018), children enrolled in Medicaid (Dreyer Gillette et al., 2014; Hampl et al., 2016) and children living in rural areas (e.g., Davis et al., 2016) or Appalachia (Hoying et al., 2016). These communities also tended to be low-income. None of the present studies conducted outside the US targeted specific marginalized populations.

Global Distribution

A plurality of studies were conducted in the US (53) across multiple states and settings. Studies were also conducted in Australia (2), Bolivia (1), Brazil (4), Canada (4), Denmark (3), Germany (4), Greece (4), Iran (4), Ireland (1), Israel (4), Italy (1), Malaysia (1), Mexico (1), New Zealand (1), Norway (4), Poland (2), Qatar (1), Singapore (1), South Korea (3), Spain (5), Sweden (3), Taiwan (1), The Netherlands (4), Turkey (2), and the UK (4).

Measures of Social Inequality

Measures of social inequality are inconsistently reported in studies. Typically, these included some combination of family income, family structure, parent education, and socioeconomic status. In the US and Canada, these also included race and ethnicity (Hispanic/non-Hispanic) and rurality. In European studies, these also included ethnicity (e.g., percent ethnic Danish in Denmark; Larsen et al., 2016). The vast majority of studies which report measures of social inequality report them as demographic categories but do not analyze them in relation to outcome variables. In the present set of studies, some examine attrition rates in relation to these measures (e.g., Boutelle et al., 2018; Hampl et al., 2016), but not weight outcomes.

Predictors, Moderators, and Mediators of Treatment

Since the previous evidence base update, several studies have explored factors that influence behavioral treatment for pediatric obesity. A complete review is beyond the scope of the current evidence base update, but the following section highlights emerging research.

Predictors and Moderators

Baseline psychopathology may be a significant predictor of treatment outcomes such that children with high levels disordered eating and elevated externalizing concerns may have less treatment success (Balantekin et al., 2017; Fornander et al., 2022). Research has also begun to explore the role that demographic variables such as race, ethnicity, and socioeconomic status may play in treatment. Studies of FBT have found that in the long term, children from marginalized racial and ethnic groups and children from low-income families appear to do equally well in FBT compared to white children and children from high-income families, but that their short-term weight change may lag (Davison et al., 2021; Eichen et al., 2020). Research in this area has also begun exploring the impact of the built environment on treatment outcomes. b. Armstrong et al. (2015) found that among rural youth participating in a behavioral weight management program, those who lived in areas with more parks had greater weight loss.

Mediators

Comparatively fewer studies have explored mediators of treatment success, but with respect to key treatment components, Boutelle et al. (2021) found that for families participating in FBT, improved stimulus control in the home and improved parental-monitoring behavior predicted treatment success after accounting for change in parent BMI. Wilfley et al. (2017) also explored mediators of treatment efficacy in FBT and found that higher treatment dose and increased social facilitation lead to greater weight loss particularly for children with severe obesity. This finding is in line with previous research that has found that high social support is associated with greater treatment success (Sampat et al., 2014).

Discussion

Summary Levels

With respect to level of evidence, FBT remains a well-established treatment for overweight and obesity in children and can now be considered well-established in adolescents and toddlers. Parent-only behavioral treatment remains well-established in children and is now also well-established among adolescents and children. Possibly effective treatments continue to include FBT-parent only for adolescents, and BWL with a family component for adolescents and children, and toddlers. Several variations of FBT and BWL can now be considered possibly effective including FBT+MI, FBT+SFM, group-based FBT, low-dose FBT, BWL+stress management, and camp-based BWL. CBT for adolescents also met criteria for possibly effective treatments. Experimental treatments included BWL, CBT, inpatient CBT, and mindful eating for adolescents, FBT+DBT, BWL, low-dose BWL with a family component, BWL+exercise, camp-based BWL and Mindfulness+nutritional counseling for adolescents and children, FBT+ exercise, group-based BWL with a family component, BWL with parent component, home-based BWL, parent-only CBT, and CBT-PEAT for children, and group-based FBT and BWL for toddlers. Treatments of questionable efficacy included BWL+peer support, school-based BWL, MI, and mindfulness for adolescents, Smartphone-based BWL for adolescents and children, parent-only BWL, BWL via newsletter, Smartphone-based BWL, CBT, CBT with a parent component, low-intensity MI, and text-based MI for children, BWL+MI for children and toddlers, and MI for toddlers.

Recommendations for Best Practice

The current evidence base update reinforces recent recommendations and guidelines that highlight the importance of behavioral treatments for pediatric obesity that are either family-based or include a strong family component. At present, FBT remains the only well-established treatment for obesity in adolescents, children, and toddlers. The current evidence base update and recent guidelines also highlight the importance of multicomponent treatments that target the home food environment. Notably, FBT targets multiple social-ecological levels known to contribute to the development and maintenance of obesity in children including child and parent behavior, family functioning, peer networks, and community and neighborhood settings (Hayes et al., 2018). It is possible that a comprehensive, multi-level approach to treatment is more effective than approaches that focus exclusively on the child even among multi-component treatments.

Future Directions

While significant progress has been made in understanding predictors, mediators, and moderators of behavioral treatments for pediatric obesity as well as in adapting these treatments to special populations including children with comorbid medical and psychiatric disorders and children from socially, politically, and economically marginalized groups, more work is needed to ensure access to appropriate care for all groups. For instance, research shows that children with obesity are at increased risk for disordered eating, but few studies assess the impact of treatment on these behaviors (Hayes et al., 2018). Research has found that participation in structured, behavioral weight loss treatment can reduce symptoms of disordered eating in children with overweight or obesity (Grammer et al., 2023; Hayes et al., 2018), but more work is needed in this area.

It was also observed that a majority of studies used BMIz or BMI-SDS as primary outcome measures. Concerns have been raised that these measures may not be sufficiently sensitive to change among children with very high BMI’s (BMI >97^th percentile) artificially reducing the apparent efficacy of clinical studies. For instance, if a 10-year-old boy with a BMI of 50 kg/m² decreased his weight by 10% over 6 months, the child’s BMI z-score would decrease by only 0.07 (Ryder et al., 2022). Future studies, particularly those that include a large percentage of children with severe obesity should consider utilizing extended BMI scores that capture the full distribution of scores above the 97^th percentile (Wei et al., 2020). Percent overweight has also been found to be more sensitive to weight change among children with severe obesity (BMI ≥120% of the 95th percentile) (Paluch et al., 2007). Finally, several studies identified in this evidence base update explored alternative settings or delivery methods. Research suggests that FBT delivered in a primary care setting or through telehealth may be acceptable and effective for the treatment of pediatric obesity, but more work is needed to identify optimal implementation strategies.

Acknowledgments

We would like to thank Leslie Ligier for assistance with article screening and initial review.

Disclosure Statement

No potential conflict of interest was reported by the author(s).

Additional information

Funding

This work was supported by the National Institute of Child Health and Human Development [under Grant F31HD106750]; and the National Heart, Lung, and Blood Institute [under Grant T32HL130357].