Quality of Life (QOL)CBH COPI JAPANNCT07061665
Cities for Better Health Childhood Obesity Prevention Initiative in JAPAN
A study testing Multi-level, Multi-component Intervention Package, Elementary schools and Parks in people with Quality of Life (QOL) and Nutrition, run by Chiba University at 1 site in Japan.
Trial summary
The goal of this interventional study is to prevent childhood obesity in children aged 6-12 years in Chiba City, Japan. The main questions it aims to answer are: Does the multi-component intervention for environments around children reduce the BMI z-score of children aged 6-12 years after one and two years? Does the… Read more about this study
- Who is it for?
- Ages 6 to 12 yearsHealthy volunteers can take part
- Conditions the study is for
- Quality of Life (QOL), Nutrition, Physical Activity
- What is being tested?
- Multi-level, Multi-component Intervention Package, Elementary schools and Parks
- Type of treatment
- Lifestyle or therapy programme
- Could I receive a placebo?
- No, everyone receives an active treatment
- How many people
- 2,200 participants
- Where
- 1 siteJapan
- Study dates
- 7 Jul 2025to Sep 2027
- Phase
- Interventional
Key requirements
Who can take part, as listed by the sponsor. Only the study team can confirm whether you are eligible, so take this list to your doctor.
- Ages 6 to 12 years
- All sexes
- Healthy volunteers accepted
- Child
Who may be able to join
- Children aged 6 to 12 years who are currently enrolled in one of the public elementary schools located within the 22 participating Junior High School District clusters in Chiba City.
- The parent or legal guardian of each child must provide written informed consent prior to participation.
- Parents or legal guardians must have sufficient Japanese language proficiency to understand study procedures, complete questionnaires, and provide accurate information during the study.
- Children must be physically and cognitively capable of participating in school- and community-based activities involved in the intervention.
- Participants must not have any medical conditions that would preclude safe participation in routine physical activities promoted by the intervention.
Who cannot join
- Children whose parents or legal guardians fail to provide complete informed consent.
- Families who withdraw consent at any point during the study period.
- Children who independently express refusal to participate, even with parental consent.
- Children with serious physical, psychological, or developmental disorders that prevent them from participating safely in the program's activities.
- Families planning to relocate outside of Chiba City during the study period, making follow-up assessment infeasible.
Trial locations and contacts
1 site in 1 country. Contact the study team or a site near you to ask about taking part.
Japan1 site, 1 recruiting
- Recruiting
Chiba University
Chiba, Chiba, 263-8522
LINGLING, PhD, +81-43-290-3177, lingling@chiba-u.jp
About this study
The goal of this interventional study is to prevent childhood obesity in children aged 6-12 years in Chiba City, Japan. The main questions it aims to answer are:
- Does the multi-component intervention for environments around children reduce the BMI z-score of children aged 6-12 years after one and two years?
- Does the multi-component intervention for environments around children improve the health-related quality of life (assessed by KIDSCREEN-10) of children aged 6-12 years after one and two years?
Read more
Researchers will compare school clusters receiving the intervention to control clusters to see if the intervention package promotes healthy eating, increases physical activity, improves health-related quality of life, and reduces obesity prevalence.
Participants will:
- Attend elementary schools within participating clusters (either the intervention or control group).
- Have baseline data collected, with follow-up assessments after one year and two years.
- Potentially participate in school-based programs (nutrition education, physical activity promotion) and community-based initiatives (park activation, supermarkets) if in an intervention cluster.
- Have their physical activity and dietary behavior assessed through self-report questionnaires.
- Conditions
- Quality of Life (QOL), Nutrition, Physical Activity, Obesity, Childhood Obesity
- Being tested
- Multi-level, Multi-component Intervention Package, Elementary schools, Parks, Ambassador Program, Home
- Keywords
- BMI, Childhood obesity, Japan, Chiba city, physical activity, nutrition, health equity, community intervention, randomized controlled trial, KIDSCREEN-10, Diet Quality Questionnaire
- Medical subject headings
- Motor Activity, Obesity, Pediatric Obesity
What participants receive
What participants receive. In a randomised study each person is assigned to one group by chance.
Multi-level, Multi-component Intervention PackageBehavioural
The CBH COPI intervention applies multi-level strategies to improve children's environments and foster healthy behaviors. The coordinated program aims to naturally promote healthy eating, physical activity, and sustained lifestyle change among children aged 6-12 in Chiba City.
Elementary schoolsBehavioural
In consultation with each elementary school, initiatives related to physical activity and diet will be implemented within the scope of the national curriculum guidelines. Super Hopscotch: Install foot-shaped signs and other markings on outdoor surfaces between the entrance/exit and school gates, as well as in the gymnasium-areas children frequent during daily school life. Place guides nearby explaining how to play and indicating difficulty levels, creating a safe and enjoyable play space. Playground Equipment Completion Card: Place numbered stickers on each piece of playground equipment, matching them to numbers on the completion card. Calendar-style Playground Equipment Completion Cards are distributed to children, who check off the numbers of the equipment they played on each day. Bug \& Find Journal: Distribute sketchbook-style "Bug \& Find Journals" to children. They sketch insects or flowers found that day.
ParksBehavioural
In consultation with Chiba City, an environment that naturally encourages healthy choices will be fostered through modifications to city-managed facilities and awareness campaigns. Standing long jump: Mark a measurable distance for standing long jump on the pavement to create a fun and challenging environment. Slalom (line walking/running): Draw lines using shapes such as triangles, circles, and squares to create a path where children can walk or run along the line. Footprint maze: Children follow colored lines and shapes drawn on the ground to reach a goal, combining visual cues with physical movement. One-leg walking (balance walking): Place footprints on a curb about 10-20 cm wide, allowing children to move forward by alternating one leg along the footprints. Stair climbing: Display multiplication tables, English words, or phrases on the risers or sides of stairs to encourage children to climb them. And 25 m run, Hopscotch, Target throwing.
Ambassador ProgramBehavioural
Children learn about food and lifestyle habits on their own, put them into action, and spread what they learn in the program to their families, schools, and communities.
Target participants: Approximately 20 fourth- and fifth-grade elementary school students.
Program components:
- Learn \& Think: Understand the fundamentals of nutrition and the importance of healthy eating.
- Experience: Apply nutrition knowledge through hands-on food-related activities.
- Share \& Inspire: Communicate what they have learned and encourage healthy eating among peers and family members.
HomeBehavioural
In consultation with each elementary school or community partner, support will be provided to foster healthy habits within each household.
•Provide tools to manage lifestyle habits, including the habit-forming app "Min-Challe," which allows anonymous teams of up to five users with a shared goal to report their daily achievements to each other by sharing photos (https://minchalle.com/).
Chiba University AcademyBehavioural
Target participants: Students from the intervention schools and the Chiba University Elementary School.
- Three lectures are planned.
- A Ken-Ken-Pa (hopscotch) course will be installed at the affiliated elementary school, or a simplified mat version will be used for hands-on activities.
- An experiential booth will allow participants to experience the intervention components, with the aim of increasing the intensity and engagement of the intervention.
| Study group | Role | What they receive |
|---|---|---|
| Obesity Prevention Intervention Group | Experimental | 11 Junior High School District (JHSD) clusters in Chiba City receive a multi-level, multi-component intervention targeting individual, environmental, and community factors for childhood obesity prevention. Receives: Behavioral: Multi-level, Multi-component Intervention Package; Behavioral: Elementary schools; Behavioral: Parks; Behavioral: Ambassador Program; Behavioral: Home; Behavioral: Chiba University Academy |
| Control Group | No intervention | 11 Junior High School District clusters in Chiba City serve as a comparator, continuing usual practices without new obesity prevention interventions from the study. |
What is being measured
The primary outcome is the main question the study is designed to answer.
Body mass index z-score (BMI-z) adjusted for age and sex
The primary outcome is the BMI z-score, calculated using the WHO 2007 Growth Reference. This metric standardizes a child's relative weight status by adjusting for both age and sex, enabling comparisons across different age groups and sexes. It represents the number of standard deviations a child's BMI is from the mean BMI of a healthy reference population. The BMI z-score allows for monitoring obesity-related changes over time and assessing the intervention's effectiveness in preventing excessive weight gain. The use of this z-score ensures consistency with international standards, facilitating global comparison of childhood obesity trends. The analysis will focus on changes in BMI z-score from baseline to 1-year and 2-year follow-ups. The BMI z-score is a continuous measure without a fixed minimum or maximum; lower values indicate lower relative adiposity, so a decrease (or a smaller increase) represents a more favorable outcome for obesity prevention.
Measured: Baseline, 1-year follow-up, 2-year follow-up (2025-2027)
Secondary outcomes (1)
Health-Related Quality of Life (HRQoL)
HRQoL will be assessed using the KIDSCREEN-10 index, a validated, self-reported measure capturing children's subjective well-being across physical, emotional, social, and school functioning. This 11-item scale uses a 5-point Likert response for each item, which is then converted into a standardized T-score, further transformed to a 0-100 scale. On this scale, higher scores indicate better perceived quality of life. Changes in KIDSCREEN-10 scores will be tracked from baseline through 1-year and 2-year follow-ups to evaluate the intervention's impact on children's overall well-being.
Measured: Baseline, 1-year follow-up, 2-year follow-up (2025-2027)
Timeline
From the start of the study to its completion; the mark is today. Estimated dates are the sponsor’s plan.
- First posted11 Jul 2025
- Study start7 Jul 2025
- Primary completionSep 2027 (estimated)
- Study completionSep 2027 (estimated)
Resources
- Official record on ClinicalTrials.govThe registry entry this page is built from, with its full change history.
- Other trials for Quality of Life (QOL)Studies of the same condition, open and under way.
- What the trial phases meanHow a treatment moves from first tests in people to approval.
More details
For doctors and researchers: how the study is designed, who runs it, and its registry IDs.
Study design
- Study type
- Interventional
- Phase
- Phase N/A
- Primary purpose
- Prevention
- Allocation
- Randomised
- Intervention model
- Parallel groups
- Model description
- This study employs a parallel interventional design. Participants, grouped by 22 school clusters (Junior High School Districts), are assigned to either an intervention group or a control group for the duration of the study. The intervention group receives a multi-level, multi-component program aimed at childhood obesity prevention, while the control group continues with usual practice. Data will be collected through repeated cross-sectional surveys at baseline, 1-year, and 2-year follow-up. Statistical analyses will use ANCOVA models, adjusted for baseline outcomes and clustering.
- Masking
- None (open label)
- Enrolment
- 2,200 participants (estimated)
Sponsor and investigators
- Lead sponsor
- Chiba University
- Sponsor type
- University, hospital or other
- Collaborators
- Novo Nordisk A/S, The Behavioural Insights Team
- Responsible party
- Principal investigator, Atsushi Nakagomi, Chiba University
IDs, dates and publications
- ClinicalTrials.gov ID
- NCT07061665
- Sponsor's protocol ID
- M10825
- Acronym
- CBH COPI JAPAN
- Status last verified
- Jul 2026
- First submitted
- 2 Jul 2025
- Last updated
- 29 Sep 2026
- Results posted
- No
- Data monitoring committee
- No
- FDA-regulated drug
- No
- FDA-regulated device
- No
- Individual data sharing
- Yes: De-identified individual data will be shared with global collaborators (Novo Nordisk A/S, The Behavioural Insights Team, Oxford University) for pooled global analyses.