Evidence brief

MEND: what the studies show

MEND (Mind, Exercise, Nutrition… Do it!) is a family-based, group-delivered childhood obesity intervention developed at the UCL Institute of Child Health. This brief covers four studies: a UK randomized controlled trial, two large service-level evaluations in England and the United States, and a US randomized trial in low-income Hispanic and Black families. Each is presented with its design, sample, dose, primary result, and limitations. Full citations are at the end.

  • 4 studies
  • 2 randomized
  • 2 at scale
  • UK + US
  • 18,000+ children enrolled

Background

Why family programs, and why MEND

The American Academy of Pediatrics' 2023 clinical practice guideline positions intensive health behavior and lifestyle treatment, delivered with the family, as the foundation of care for children with obesity.[5] CDC maintains a list of recognized Family Healthy Weight Programs that meet its screening criteria for evidence, safety, and readiness; recognized programs deliver at least 26 hours of contact over 2 to 12 months. MEND is on that list, and the YMCA's Healthy Weight and Your Child curriculum is adapted from it.[6]

CDC's COMMIT initiative with the National Association of Community Health Centers is implementing MEND in federally qualified health centers; CDC's fact sheet describes the program as having reached more than 100,000 children and families.[7]

CDCCDC-recognized programBuilt on MEND, a CDC-recognized Family Healthy Weight Program

The program. MEND runs for about ten weeks with two group sessions a week, and a parent or caregiver attends with the child. Sessions combine nutrition education, physical activity, and behavior-change techniques such as goal-setting, problem-solving, positive reinforcement, and changing cues at home. It was designed for community settings (schools, leisure centres, clinics) and delivery by trained health, physical-activity, and social-care staff rather than specialists.[1][2] The current US version delivers 35 contact hours.[3]

How to read the outcomes. zBMI is BMI standardized for age and sex; the UK studies use the UK 1990 reference and the US studies use CDC 2000, so z-scores are not directly comparable across countries. %BMIp95, used in TX CORD, expresses BMI as a percentage of the 95th percentile and behaves better than zBMI in children with severe obesity.

The studies

Four studies, presented the way a reviewer would want them.

Two randomized trials establish efficacy against a comparator. Two service-level evaluations show what happens when the same program is delivered at scale by local organisations, without research staff.

Randomized controlled trial, United Kingdom

Sacher et al. · Obesity 2010 · [1] · ISRCTN 30238779

Design
Randomized trial of MEND versus a waiting-list control that received the program six months later. Delivered at five community sites by separate teams; all measurements taken in community settings.
Participants
116 children aged 8 to 12 with obesity (BMI at or above the 98th percentile, UK 1990 reference), each with at least one parent or carer able to attend every session.
Intervention
Eighteen two-hour group sessions, twice a week, in sports centres and schools, combining education and physical activity, followed by a 12-week free family swimming pass. Mean attendance was 86%.
Outcomes
Waist circumference, BMI, body composition, physical activity, sedentary time, cardiovascular fitness, and self-esteem at baseline and 6 months; follow-up at 12 months from baseline.
Results

At 6 months, adjusted for baseline, the intervention group had lower waist circumference (−4.1 cm; −0.37 z) and BMI (−1.2 kg/m²; −0.24 z) than controls, all P < 0.0001. Fat mass, recovery heart rate, physical activity, sedentary time, and global self-esteem also favoured the intervention. Controls did not change.

At 12 months from baseline, the intervention group's waist and BMI z-scores were 0.47 and 0.23 below baseline, and the fitness, activity, and self-esteem gains held.

Limitations
Small sample. The wait-list design ends the between-group comparison at 6 months, so the 12-month result is within-group. The trial was run by the program's developers, which the authors declare.

MEND beat wait-list on both adiposity measures at 6 months.

BMI z-score-0.24 Waist circumference z-score-0.37 -0.5 -0.4 -0.3 -0.2 -0.1 0 DIFFERENCE VS CONTROL AT 6 MONTHS, Z-SCORE UNITS
Fig. 1Between-group difference at 6 months, intervention minus control, adjusted for baseline. n = 116. Both P < 0.0001. Source: [1].

Service-level evaluation at scale, England

Fagg et al. · International Journal of Obesity 2014 · [2] · NIHR-funded, open access

Design
Uncontrolled evaluation of prospective service data collected by delivery partners between January 2007 and December 2010. Multilevel models (children nested in programmes) adjusted for baseline values; multiple imputation for missing covariates; sensitivity analyses on complete cases.
Participants
21,132 families referred or self-referred; 13,998 attended; 9,563 children had complete before-and-after BMI data, across 1,788 programmes in every region of England. Eligible children were 7 to 13 and above the 91st BMI centile; most were above the 98th. Mean age 10.
Intervention
Twenty sessions over ten weeks, with a parent or carer required at every session, delivered by local community organisations trained by MEND Central. Three-quarters of children attended more than 75% of sessions.
Results

After adjustment, BMI fell 0.76 kg/m² and zBMI fell 0.18; self-esteem rose 3.53 points (about half a standard deviation) and parent-reported psychological distress (SDQ) fell 2.65 points (about a third of an SD); all P < 0.0001.

Among 8-to-12-year-olds with obesity, BMI fell 0.79 kg/m² (95% CI 0.74–0.84) under service conditions versus 1.04 (0.79–1.29) in the trial; the difference was not statistically significant.

Equity signal. Gains were smaller for children from less advantaged backgrounds and for Asian compared with white children, and larger with more sessions attended and in smaller groups. The authors warn the program could widen inequalities unless adapted.

Limitations
No control group, so associations are not effectiveness estimates. Data were collected for service delivery, not research: 33–63% of some covariates were missing and imputed. No follow-up beyond the end of the programme. Program developers had no access to the data.

The effect largely held when local organisations delivered it.

Randomized trial1.04 (0.79–1.29) Service delivery across England0.79 (0.74–0.84) 0 0.25 0.5 0.75 1 1.25 BMI REDUCTION, KG/M² (95% CI), ADJUSTED
Fig. 2BMI reduction over the programme in 8-to-12-year-olds with obesity, adjusted for baseline BMI, age, sex, ethnicity, and housing tenure. The trial-versus-service difference was not statistically significant. Source: [2].

Service-level evaluation at scale, United States

Sacher et al. · International Journal of Obesity 2019 · [3]

Design
Uncontrolled repeated-measures evaluation of MEND 7–13 provided as a primary-care child weight-management service. Longitudinal multivariate imputation for missing data; peer effects estimated with an instrumental-variables approach and group fixed effects.
Participants
3,782 children with overweight or obesity attending 415 programs in eight US states; 2,482 (65.6%) had complete zBMI data. Programs targeted low-income, ethnically diverse families and were free to attend, funded by health plans, foundations, and public health departments.
Intervention
Twice-weekly sessions for ten consecutive weeks, 35 contact hours, delivered to groups of children with accompanying parents or caregivers.
Results

At 10 weeks, BMI fell 0.49 kg/m² (95% CI −0.67 to −0.31) and zBMI fell 0.06 (−0.08 to −0.05), with benefits in cardiovascular fitness and psychological outcomes. Mean attendance was 73.9% and retention 88.5%.

Peer effect. A child's zBMI reduction was larger when peers in the same group also improved (B = 0.78, 95% CI 0.03–1.53, P = 0.04), the first quantified peer effect in an up-scaled US child weight-management program.

Limitations
No control group. A third of children lacked complete outcome data. The zBMI change is smaller than in England; the populations, growth references, and versions differ, so the two are not directly comparable. Several authors work with the organisation that delivers MEND in North America, which they declare.

Low-income families attended, and most stayed to the end.

Mean session attendance73.9% Retention to end of program88.5% 0% 25% 50% 75% 100%
Fig. 3Mean program attendance and retention across 415 MEND 7–13 programs in eight US states, n = 3,782. Source: [3].

TX CORD randomized trial, Texas

Butte et al. · Obesity 2017 · [4] · design paper Hoelscher et al. 2015 [8]

Design
Randomized trial in Houston and Austin comparing a 12-month community-centred program (MEND 2–5 for ages 2 to 5; MEND/CATCH 6–12 for ages 6 to 12) with a primary-care-centred program built on the AAP's Next Steps materials. Stratified by age group; outcomes at baseline, 3 months (Intensive Phase), and 12 months (Transition Phase).
Participants
549 Hispanic and Black children aged 2 to 12 with BMI at or above the 85th percentile, recruited through primary care; 86% Hispanic; 80% from households earning under $25,000.
Dose
27 contact hours for ages 2 to 5 and 121.5 for ages 6 to 12, versus 8 hours in the primary-care arm.
Results

For ages 6 to 8, MEND/CATCH produced a larger %BMIp95 improvement than the primary-care program during the Intensive Phase: −1.94 percentage points (95% CI −3.88 to −0.01; P = 0.05). For ages 9 to 12 the estimate was −1.38 (−2.87 to 0.16; P = 0.07). For ages 2 to 5 there was no differential effect.

Attendance averaged 52% in the Intensive Phase and 22% in the Transition Phase, and more attendance meant more %BMIp95 reduction (P < 0.05). During the Transition Phase, %BMIp95 was maintained or rebounded in both arms, so by 12 months the community program was no longer more efficacious than the primary-care program. Twelve-month retention was 54%, 78%, and 73% in the intervention arm versus 82%, 85%, and 81% in the comparison arm for ages 2–5, 6–8, and 9–12.

Limitations
The 3-month advantage did not persist to 12 months. A 121.5-hour dose proved hard for families to attend, and the comparison arm received real counselling, not usual care. The ages-6-to-8 confidence interval only just excludes zero.

A significant advantage for ages 6–8; borderline for 9–12.

NO DIFFERENCE Ages 6–8 · P = 0.05-1.94 (-3.88, -0.01) Ages 9–12 · P = 0.07-1.38 (-2.87, +0.16) -4 -3 -2 -1 0 1 %BMIp95, PERCENTAGE POINTS VS PRIMARY-CARE ARM, 3 MONTHS
Fig. 4Difference in %BMIp95 change, MEND/CATCH minus primary-care program, at the 3-month Intensive Phase assessment, by age stratum. n = 549. Source: [4].

Attendance fell by more than half once the intensive phase ended.

Intensive Phase, months 0–352% Transition Phase, months 4–1222% 0% 25% 50% 75% 100%
Fig. 5Mean session attendance in the community-program arm by study phase. Source: [4].

Side by side

The same program, four settings.

Table 1. Comparison of the four MEND studies
StudyDesignSettingSampleAgesDosePrimary resultFollow-upMain limitation
Sacher 2010 [1]RCT vs wait-listUK, 5 community sites1168–1218 × 2 h over 9 wks + swim passzBMI −0.24 vs control, 6 mo12 mo, within-groupSmall; developer-led
Fagg 2014 [2]Uncontrolled service evaluationEngland, 1,788 programmes13,998 attended · 9,563 analysed7–1320 sessions / 10 wkszBMI −0.18, 10 wksNone after programmeNo control; imputed covariates
Sacher 2019 [3]Uncontrolled repeated measures8 US states, 415 programs3,782 · 2,482 analysed7–1320 sessions / 10 wks · 35 hzBMI −0.06, 10 wksNone after programNo control; 34% incomplete
Butte 2017 [4]RCT vs primary-care programHouston & Austin, TX5492–12121.5 h (ages 6–12) vs 8 h%BMIp95 −1.94 pts, ages 6–8, 3 mo12 mo: not sustained vs comparisonAttendance 52% → 22%

Table 1. zBMI uses the UK 1990 reference in [1,2] and the CDC 2000 reference in [3]; %BMIp95 is BMI as a percentage of the CDC 95th percentile. Within-person changes in the uncontrolled studies are not effect sizes against a comparator.

Longer term. An uncontrolled follow-up of 165 children measured 2.4 years after MEND 7–13 in England found improvements on all outcomes except BMI z-score overall; boys improved on BMI z, waist z, and psychometric measures, girls only on body esteem.[9] Longer-term controlled data do not exist for any of the four studies above.

Reading across the studies

What this means for a caregiver-facing digital translation

The mechanisms are the evidence.

Every study links outcome to exposure: session attendance in England and Texas, smaller groups in England, peers who improve in the US. The open question for any digital format is whether those mechanisms survive without a room and a facilitator, and that has to be tested rather than assumed.

Attendance is the constraint the evidence keeps exposing.

86% in a supported trial, 74% under US service conditions, 52% and then 22% across a 12-month program. Reducing travel, scheduling, and time burden is a plausible lever for the families who never enrol or drop out, not a proven one.

Equity is not automatic.

The England evaluation found smaller gains in less advantaged families and warned of widened inequalities. A translation built for Medicaid-enrolled rural families has to measure whether it narrows that gap, and report results by language and subgroup rather than by average alone.

Short programs show short-term effects.

Ten-week outcomes are consistent across settings; twelve-month maintenance is where TX CORD lost its advantage. Maintenance content and low-burden follow-up matter as much as the initial curriculum.

What CoachMEND claims, and what it doesn't. CoachMEND preserves each MEND lesson's learning objective, behavior-change mechanism, key teaching content, and intended caregiver action in a caregiver-facing, smartphone-delivered format. It does not claim equivalence of delivery format, contact hours, or dose, and none of the figures on this page are results for CoachMEND.

References

Sources

  1. [1]
    Sacher PM, Kolotourou M, Chadwick PM, Cole TJ, Lawson MS, Lucas A, Singhal A. Randomized controlled trial of the MEND program: a family-based community intervention for childhood obesity. Obesity (Silver Spring). 2010;18(Suppl 1):S62–S68. doi:10.1038/oby.2009.433
  2. [2]
    Fagg J, Chadwick P, Cole TJ, Cummins S, Goldstein H, Lewis H, Morris S, Radley D, Sacher P, Law C. From trial to population: a study of a family-based community intervention for childhood overweight implemented at scale. Int J Obes. 2014;38(10):1343–1349. doi:10.1038/ijo.2014.103
  3. [3]
    Sacher PM, Kolotourou M, Poupakis S, Chadwick P, Radley D, Fagg J. Addressing childhood obesity in low-income, ethnically diverse families: outcomes and peer effects of MEND 7–13 when delivered at scale in US communities. Int J Obes. 2019;43(1):91–102. doi:10.1038/s41366-018-0158-2
  4. [4]
    Butte NF, Hoelscher DM, Barlow SE, Pont S, Durand C, Vandewater EA, et al. Efficacy of a community- versus primary care-centered program for childhood obesity: TX CORD RCT. Obesity (Silver Spring). 2017;25(9):1584–1593. doi:10.1002/oby.21929
  5. [5]
    Hampl SE, Hassink SG, Skinner AC, et al. Clinical practice guideline for the evaluation and treatment of children and adolescents with obesity. Pediatrics. 2023;151(2):e2022060640. doi:10.1542/peds.2022-060640
  6. [6]
    Centers for Disease Control and Prevention. CDC-Recognized Family Healthy Weight Programs. Updated December 4, 2025. cdc.gov/family-healthy-weight/php/recognized-programs
  7. [7]
    Centers for Disease Control and Prevention. COMMIT! Childhood Obesity Management with MEND Implementation Teams (fact sheet). cdc.gov/obesity/initiatives/commit
  8. [8]
    Hoelscher DM, Butte NF, Barlow S, Vandewater EA, Sharma SV, Huang T, et al. Incorporating primary and secondary prevention approaches to address childhood obesity prevention and treatment in a low-income, ethnically diverse population: study design and demographic data from the Texas Childhood Obesity Research Demonstration (TX CORD) study. Child Obes. 2015;11(1):71–91. doi:10.1089/chi.2014.0084
  9. [9]
    Kolotourou M, Radley D, Gammon C, Smith L, Chadwick P, Sacher PM. Long-term outcomes following the MEND 7–13 child weight management program. Child Obes. 2015;11:325–330. doi:10.1089/chi.2014.0092
  10. [10]
    Law C, Cole T, Cummins S, Fagg J, Morris S, Roberts H. A pragmatic evaluation of a family-based intervention for childhood overweight and obesity. Public Health Res. 2014;2(5). doi:10.3310/phr02050
  11. [11]
    Fagg J, Cole TJ, Cummins S, Goldstein H, Morris S, Radley D, et al. After the RCT: who comes to a family-based intervention for childhood overweight or obesity when it is implemented at scale in the community? J Epidemiol Community Health. 2015;69:142–148. doi:10.1136/jech-2014-204155