Evaluation of a Multicomponent Early Intervention for Childhood Obesity Prevention in Vulnerable Families (Bambú)

Evaluation of a Tailored Multicomponent Early Intervention for Childhood Obesity Prevention in Vulnerable Families (Bambú Project): Randomized Controlled Trial With a Hybrid Type 1 Effectiveness-implementation Design

Childhood obesity is a public health concern. Evidence-based, multicomponent, parenting interventions targeting early childhood and adapted to families' socioeconomic context are needed to prevent childhood obesity.

This study aims to evaluate the effectiveness of an early intervention in primary care for the prevention of childhood obesity, targeting vulnerable families where the mother and/or the father has overweight or obesity.

More specifically, the primary aim of this study is to evaluate the effectiveness the intervention to maintain a healthy weight in children aged 6 months to 3 years, measured by the BMI-for-age z-score at baseline, 6, 12, and 18 months, compared to usual care.

The study also aims to evaluate the effectiveness of the intervention, compared to usual care, for: promoting responsive feeding, improving dietary intake, improving parents' and children's physical activity levels, improving parents' eating styles, and improving children's sleep.

Finally, the study aims to determine the feasibility of implementing the intervention, and to identify factors influencing change and contextual factors in the implementation process.

A pragmatic cluster randomized controlled trial will be conducted. Approximately 526 families (parent-child family dyads) will be recruited, belonging to 76 primary care centers. Primary care centers will be randomly assigned to either an intervention or control group.

The intervention has been previously co-designed with families and healthcare professionals, and consists of five weekly sessions and 4 monthly sessions, lasting 2 hours each. It will be delivered by previously trained healthcare professionals or by members of the research team, depending on the preferences and availability of the primary care center professionals. Approximately 38 intervention face-to-face groups will be conducted, one in each primary care center allocated to the intervention group.

The study will be conducted in Catalonia, Andalusia and the Balearic Islands (Spain).

Effectiveness outcomes include child body mass index (BMI) z-score, parent feeding practices (measured with the Feeding Practices and Structure Questionnaire), child dietary intake (measured with the multiple-pass 24-hour recall), parents' eating behaviours (measured with the Dutch Eating Behavior Questionnaire), child movement (measured with the Movement Behavior Questionnaire), parents' movement behaviours (measured with the Brief Physical Activity Assessment Tool), and child sleep (measured with selected items from the Brief Infant Sleep Questionnaire).

Implementation and feasibility outcomes will be assessed through interviews during and at the end of the intervention, and through attendance sheets and a final satisfaction questionnaire.

This study will provide pioneering insights into the implementation and effectiveness of this intervention within the public healthcare system in Spain. This will allow the potential implementation in the future at a larger scale.

Study Overview

• Status: Recruiting
• Conditions: Children; Obesity & Overweight; Vulnerable Families; Families With Infants
• Intervention / Treatment: Behavioral: Bambú program

• Study Type: Interventional
• Enrollment (Estimated): 526
• Phase: Not Applicable

Contacts and Locations

• Study Contact: Name: Helena Vall Roqué, PhD; Phone Number: +34932076608; Email: hvall@fadq.org
• Study Contact Backup: Name: Nuria Hidalgo; Email: nhidalgo@fadq.org

Study Locations

• Spain
  • Palma de Mallorca, Spain, 07002
    • Recruiting
    • Atenció Primària de Mallorca
    • Contact: Joana Ripoll Amengual; Phone Number: +34626748937; Email: joana.ripoll@ibsalut.es
  • Seville, Spain, 41008
    • Recruiting
    • Servicio Andaluz de Salud
    • Contact: Rosario Vigo Ortega; Phone Number: +34955016700; Email: rosario.vigo.sspa@juntadeandalucia.es
  • Catalonia
    • Barcelona, Catalonia, Spain, 08037
      • Recruiting
      • Fundación Avedis Donabedian Para la Mejora de la Calidad Asistencial
      • Contact: Helena Vall Roqué, PhD; Phone Number: +34 932076608; Email: hvall@fadq.org
      • Contact: Carola Orrego, PhD; Phone Number: +34 932076608; Email: corrego@fadq.org

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: Child; Adult; Older Adult
• Accepts Healthy Volunteers: Yes

Description

Inclusion Criteria:

• Mothers and/or fathers aged 18 years or older.
• Primary caregivers of a healthy child aged 6 months to 3 years, born at term (≥37 weeks of gestation).
• At least one parent with overweight or obesity (as defined by BMI criteria).
• Families in a situation of vulnerability, defined as meeting ≥2 of the following criteria: (1) Low educational level of at least one parent (≤ lower secondary education or equivalent); (2) Precarious employment situation during the past year, (3) Perceived financial difficulties during the past year; (4) Insecure or unstable housing conditions; (5) Single-parent family or prolonged absence of one of the primary caregivers; (6) Recent immigration (≤10 years) without a stable support network or with language barriers.

Exclusion Criteria:

• Parents of a child aged 6 months to 3 years with low birth weight (<2500 g)
• Parents of a child aged 6 months to 3 years from a multiple birth (e.g., twins, triplets)
• Parents/caregivers of a child aged 6 months to 3 years with congenital conditions, chronic diseases, or severe disabilities that may affect feeding, growth, or participation in the study
• Parents or caregivers with severe physical or mental health conditions that would limit their ability to participate in the intervention or assessments
• Families planning to move out of the study area during the study period

Study Plan

How is the study designed?

Design Details

• Primary Purpose: Prevention
• Allocation: Randomized
• Interventional Model: Parallel Assignment
• Masking: None (Open Label)

Number of Arms

2

Arms and Interventions

Participant Group / Arm	Intervention / Treatment
Experimental: Intervention group (Bambú program); This arm will include all primary care centers assigned to the intervention group. All participants (parents) within these centers will receive the Bambú intervention. They will participate in a 9-session group-based face-to-face intervention. Sessions will last 2 hours. The first 5 sessions will be delivered weekly and the following 4 sessions will be delivered monthly. They will be delivered at primary care centers in Catalonia, Andalusia and Balearic Islands. They will be led by two professionals, either healthcare professionals working at the primary care center (who will be previously trained) or by members of the research team. The following main topics will be covered in the program: (1) nutrition; (2) physical activity and interactive play; (3) emotion regulation; (4) positive parenting; (5) child sleep; and (6) community support networks. Approximately 38 groups will be conducted, and each of them will include around 7 families.	Behavioral: Bambú program; The Bambú program is a face-to-face 9-session group-based intervention for parents of children aged 6 months - 3.11 years, where at least one parent has overweight or obesity. Sessions last 2 hours. The first five sessions are delivered weekly and the other four sessions are delivered monthly. Sessions are led by two trained co-leaders (training includes two online sessions and access to a virtual platform with all intervention materials). The program covers six main topics: (1) nutrition: feeding practices and dietary recommendations; (2) physical activity and interactive play; (3) emotion regulation skills and techniques; (4) positive parenting; (5) child sleep; and (6) community support networks. The intervention is structured and includes video visualization and interactive activities. The program has been previously co-designed with families and healthcare professionals aiming to target it to the needs and preferences of vulnerable families with overweight or obesity.
No Intervention: Control group; The control group will not receive the intervention. Families who are assigned to the control group will receive their usual care. No restrictions will be placed on families or primary care centers regarding access to other training and support services during the course of the study, but this information will be monitored as a potential confounder. Primary care centers who are assigned to the intervention group will be asked not to share the intervention contents with other centers who are in the control group before the end of the study.

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Changes from baseline to post-intervention and each follow-up in Body Mass Index (BMI) z-score	The BMI z-scored will be measured using the WHO Child Growth Standards. "At risk for overweight," "overweight," and "childhood obesity" for children under five are defined as BMI z-scores >1 and ≤2, >2 and ≤3, or >3 standard deviations above the median established by WHO growth standards, respectively.	Measured to the intervention and control group at baseline (prior to program initiation) and after the intervention (at 6, 12 and 18 months after baseline)

Secondary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Changes from baseline to post-intervention and each follow-up in child dietary intake	Child dietary intake will be measured using the multiple-pass 24-hour recall, which is a brief interview that will be conducted by healthcare professionals who participate in the project.	Administered to the intervention and control group at baseline (prior to program initiation) and after the intervention (at 6, 12 and 18 months after baseline)
Changes from baseline to post-intervention and each follow-up in the Feeding Practices and Structure Questionnaire (FPSQ)	The Feeding Practices and Structure Questionnaire is a self-administered questionnaire that measures parental feeding practices, specifically maternal responsiveness to children's hunger/satiety signals facilitated by routine and structure in feeding.	Administered to the intervention and control group at baseline (prior to program initiation) and after the intervention (at 6, 12 and 18 months after baseline)
Changes from baseline to post-intervention and each follow-up in the Movement Behavior Questionnaire (MBQ)	The Movement Behavior Questionnaire is a self-administered questionnaire that measures physical activity, screen time and sleep in infants, toddlers and preschoolers.	Administered to the intervention and control group at baseline (prior to program initiation) and after the intervention (at 6, 12 and 18 months after baseline)
Changes from baseline to post-intervention and each follow-up in Brief Physical Activity Assessment Tool (BPAAT)	The Brief Physical Activity Assessment Tool is a self-administered 2-item questionnaire to identify "inactive" patients in primary care settings.	Administered to the intervention and control group at baseline (prior to program initiation) and after the intervention (at 6, 12 and 18 months after baseline)
Changes from baseline to post-intervention and each follow-up in the Dutch Eating Behavior Questionnaire (DEBQ)	Parents' eating patterns will be measured with the Dutch Eating Behavior Questionnaire. This is a self-administered questionnaire designed to assess three distinct eating styles: emotional eating, external eating, and cognitive restraint.	Administered to the intervention and control group at baseline (prior to program initiation) and after the intervention (at 6, 12 and 18 months after baseline)
Changes from baseline to post-intervention and each follow-up in infant sleep	Selected items (applicable to the whole children's age range included in the study) from the Brief Infant Sleep Questionnaire (BISQ) will be used to measure child sleep.	Administered to the intervention and control group at baseline (prior to program initiation) and after the intervention (at 6, 12 and 18 months after baseline)
Percentage of parents engaging with and finishing the program	Parents' attendance will be recorded after each session using attendance sheets. These data will be used to calculate overall compliance and engagement across the full intervention period.	Through intervention completion (9 sessions, approximately 6 months)
Parents' acceptability and satisfaction with the program (evaluated with a Final Participant Satisfaction Questionnaire)	Parents' acceptability and satisfaction with the program will be assessed with a Final Participant Satisfaction Questionnaire. Data will be collected after the last session of the intervention.	Administered to the intervention group at intervention completion (approximately 6 months after baseline)
Group leaders' fidelity with the program (evaluated with the Leader Checklist)	Fidelity with the program will be assessed after each session using the Leader Checklist completed by group leaders. Fidelity will be summarized across all sessions to evaluate adherence to the intervention protocol.	Through intervention completion (9 sessions, approximately 6 months)
Parents' and group leaders' overall experiences with the program (evaluated with individual interviews and focus groups)	Semi-structured individual interviews and focus groups will be conducted with parents and group leaders during the intervention and after the final session to explore barriers and facilitators, as well as acceptability, adoption, appropriateness, feasibility, penetration, and sustainability of the intervention.	Through intervention completion (approximately 6 months)

Collaborators and Investigators

• Sponsor: Helena Vall Roqué
• Collaborators: Loyola University; Hospital Costa del Sol; Andalusian Health Service; Hospital Universitari Son Espases (Palma de Mallorca. Spain); Primary Care Research Unit of Mallorca, Balearic Islands Health Service, Palma; Research Group on Primary Care and Promotion of the Balearic Islands Community (Grapp-CAIB); Health Research Institute of the Balearic Islands (IdISBa), Palma; General Directorate of Public Health, Balearic Island, Palma; Public health research group of the Balearic Islands (GISPIB)
• Investigators: Principal Investigator: Carola Orrego, PhD, Avedis Donabedian Research Institute

Publications and helpful links

General Publications

• Blake-Lamb TL, Locks LM, Perkins ME, Woo Baidal JA, Cheng ER, Taveras EM. Interventions for Childhood Obesity in the First 1,000 Days A Systematic Review. Am J Prev Med. 2016 Jun;50(6):780-789. doi: 10.1016/j.amepre.2015.11.010. Epub 2016 Feb 22.
• Epstein LH, Wilfley DE, Kilanowski C, Quattrin T, Cook SR, Eneli IU, Geller N, Lew D, Wallendorf M, Dore P, Paluch RA, Schechtman KB. Family-Based Behavioral Treatment for Childhood Obesity Implemented in Pediatric Primary Care: A Randomized Clinical Trial. JAMA. 2023 Jun 13;329(22):1947-1956. doi: 10.1001/jama.2023.8061.
• Guerra Toro HI,Jaramillo AP,Caceres VM
• Ciampa PJ, Kumar D, Barkin SL, Sanders LM, Yin HS, Perrin EM, Rothman RL. Interventions aimed at decreasing obesity in children younger than 2 years: a systematic review. Arch Pediatr Adolesc Med. 2010 Dec;164(12):1098-104. doi: 10.1001/archpediatrics.2010.232.

Helpful Links

• Website of the project

Study record dates

Study Major Dates

• Study Start (Actual): March 2, 2026
• Primary Completion (Estimated): April 1, 2028
• Study Completion (Estimated): June 1, 2028

Study Registration Dates

• First Submitted: March 31, 2026
• First Submitted That Met QC Criteria: April 7, 2026
• First Posted (Actual): April 14, 2026

Study Record Updates

• Last Update Posted (Actual): April 14, 2026
• Last Update Submitted That Met QC Criteria: April 7, 2026
• Last Verified: April 1, 2026

More Information

Terms related to this study

• Keywords: Randomized controlled trial; Primary health care; Prevention; Early intervention; Vulnerable populations; Pediatric obesity; Parenting interventions
• Additional Relevant MeSH Terms: Nutrition Disorders; Overnutrition; Body Weight; Pathological Conditions, Signs and Symptoms; Nutritional and Metabolic Diseases; Signs and Symptoms; Overweight; Obesity; Pediatric Obesity
• Other Study ID Numbers: PI24/01033; 24/291-P (Other Identifier: Ethics Committee for Research with Medicines (CEIm) of IDIAP Jordi Gol)

Plan for Individual participant data (IPD)

• Plan to Share Individual Participant Data (IPD)?: NO

Drug and device information, study documents

• Studies a U.S. FDA-regulated drug product: No
• Studies a U.S. FDA-regulated device product: No