Obesity
Conditions
Keywords
obesity, nutrition, physical activity, preschool, child care centers, policy-system-environment intervention
Brief summary
Childhood obesity is a national epidemic that disproportionately burdens low income and ethnic minority populations. By preschool, nearly one-third of low income children are already overweight or obese, setting the stage for adverse health outcomes over their life course. Evidence is mounting that individual-focused, single-component interventions fail to produce long-term population-level changes in obesity-related outcomes. Evidence increasingly supports creating entire environments (e.g., schools) in which the healthy choice is the default option. The investigators will conduct a pragmatic cluster randomized trial to evaluate the effectiveness of a multilevel (organization, teacher, parent, child) intervention to support healthy eating and physical activity in preschools. The study is being conducted in partnership with Child Care Resource Center (CCRC), a non-profit organization dedicated to ensuring that all children receive high quality preschool experiences. The investigators will randomly assign 60 preschool sites (stratified by size), located in underserved areas of Los Angeles, to the intervention or a usual practice control conditions. The investigators will evaluate the effectiveness of the intervention on child BMI z-scores (primary outcome) and parent-reported child nutrition and physical activity (secondary outcomes). The investigators will systematically examine the implementation process to understand factors that may facilitate or hinder intervention uptake and success. The findings from this work will be critical for informing future dissemination efforts.
Detailed description
This study involves a 2-group design with stratified cluster randomization at the level of the preschool. The investigators will recruit 60 preschools from LA County's most vulnerable communities, stratified by size (large, small). The investigators will randomly select pairs of schools from each stratum and randomly assign one member of each pair to the intervention or control conditions. Given the 10-month instructional year (Sept. 1-June 30), preschools will be recruited in three cohorts over three instructional years (\ 20 schools per cohort). To control for time trends in outcomes, the randomization protocol will be implemented independently within each cohort. Baseline data collection, conducted in the first six weeks of the school year, will include surveys (site directors, teachers, parents), anthropometric measures (children), preschool policy reviews and direct observation in preschools including child-level eating behavior and physical activity. The multilevel intervention will be initiated immediately following baseline data collection and will consist of 1) establishment of organizational policies to support healthy nutrition and physical activity, 2) integration of nutrition and physical activity content into curricula 3) supports for teachers and staff to model healthy behavior, and 4) engagement of parents as partners in implementing healthy policies in preschool and at home. Implementation measures will be collected throughout the project period. Follow-up data collection, in the last four-six weeks of the school year, will mirror baseline data collection. Study Hypotheses: 1. Children at intervention schools will gain less weight relative to height gains compared to children at control schools, resulting in lower mean BMI z-scores at follow-up (effectiveness). Outcomes will be assessed in the overall sample and among the subset of children who are overweight or obese at baseline. 2. Intervention preschools will have greater implementation of healthy nutrition and physical activity policies and practices at follow-up compared to control preschools. The primary effectiveness outcome will be child age-and sex-adjusted BMI z-score. The investigators will obtain baseline data on 1,630 children, 815 per condition, 60 preschool site directors and approximately 135 teachers. Estimating 80% child retention at follow-up, the investigators anticipate having follow-up data on 1,304 children, 652 per study arm. Data will also be collected from the parents of participating children at baseline and follow-up.
Interventions
BEHAVIORALMulti-level preschool obesity control intervention
The multi-level intervention is a preschool-based program that integrates healthy nutrition and physical activity policies and practices into preschool operations via the Sesame Street Healthy Habits for Life curriculum. In addition to the curriculum, the intervention includes coaching sessions to enhance teacher lesson planning to routinely include nutrition and physical activity; as well as assist preschool site directors with implementing policy changes and parent engagement sessions.
Sponsors
University of California, Los Angeles
Study design
Allocation
RANDOMIZED
Intervention model
PARALLEL
Primary purpose
OTHER
Masking
NONE
Eligibility
Sex/Gender
ALL
Age
30 Months to No maximum
Healthy volunteers
Yes
Inclusion criteria
Preschool Sites: * Must be in CCRC network of preschools * Have 20 or more preschool aged children (2.5-5 years old) in attendance at site * Children must eat at least one meal on-site per school day * Must have at least one preschool classroom Providers (Teachers and Preschool Site Directors): * Teachers must teach a preschool class at participating preschool * Be able to provide informed consent Parents and Children: * Child must be 2.5-5 years old and enrolled in the participating preschool * Child primary caregiver must have at least one child 2.5-5 years old that is enrolled in the preschool * Child primary care giver must be able to read and write in English or Spanish
Exclusion criteria
Preschool Sites: * Have less than 20 preschool aged children (2.5-5 years old) enrolled. * Do not have a preschool classroom * Are not in the CCRC network * Preschools that are based in a family-home or serve special needs children exclusively * Children do not eat at least one meal on-site per school day Providers (Teachers and Preschool Site Directors): -Teachers not currently teaching a preschool class Parents and Children: * Child primary care giver unable to read or write in English or Spanish * Primary care giver who does not have a child currently enrolled in a preschool class
Design outcomes
Primary
| Measure | Time frame | Description |
|---|---|---|
| Child BMI Z-score | Measured pre-intervention at the beginning of the school year and post-intervention at the end of the school year (approximately 10 months later) | Height and weight of preschool children were measured by trained research staff. These data were used to calculate children's body mass index (BMI) scores. The BMI Z-score is a measure calculated from a child's height and weight that indicates how a child's BMI compares with the BMI of a reference population of U.S. children of the same age and sex. The reference population is based on Center for Disease Control and Prevention (CDC) pediatric growth charts and the BMI Z-score is calculated using a CDC-provided computer program. A Z-score of 0 corresponds to the mean BMI of the reference population. A Z-score of +1 corresponds to a BMI that is one standard deviation above the mean of the reference population, and a Z-score of -1 represents a BMI that is one standard deviation below the mean of the reference population. When used as a measure of obesity risk, a lower Z-score is considered a better outcome. |
Secondary
| Measure | Time frame | Description |
|---|---|---|
| Frequency of Physical Activity | Measured pre-intervention at the beginning of the school year and post-intervention at the end of the school year (approximately 10 months later) | Parents completed surveys regarding children's physical activity and nutrition. For frequency of physical activity, the following question was asked: During the past 7 days, on how many days was your child physically active for a total of at least 60 minutes per day? |
| Teacher Nutrition Behaviors | 4 weeks post intervention | Teacher nutrition will be measured via self-report of dietary intake. |
| Percentage of Children Who Eat Fruit Once a Day | Measured pre-intervention at the beginning of the school year and post-intervention at the end of the school year (approximately 10 months later) | Parents completed surveys regarding children's physical activity and nutrition. For frequency of fruit consumption, the following question was asked: How often does your child eat... fruit? Include fresh, frozen, or canned fruit. DO NOT include juices. The response is dichotomized as at least once a day versus less than once a day. |
| Nutrition and Physical Activity Policies and Practices at Preschool Site Level | 4 weeks post intervention | Nutrition and physical activity policies of the preschool will be assessed via in-person all day observations of one preschool classroom per site. Trained research staff will conduct these observations during an on-site visit to the center. Additionally, preschool site directors will complete a nutrition and physical activity policy and practice survey to assess center nutrition and physical activity policies. |
| Percentage of Children Who Eat Vegetables Once a Day | Measured pre-intervention at the beginning of the school year and post-intervention at the end of the school year (approximately 10 months later) | Parents completed surveys regarding children's physical activity and nutrition. For frequency of vegetable consumption, the following question was asked: How often does your child eat... vegetables? DO NOT count potatoes, or beans. The response is dichotomized as at least once a day versus less than once a day. |
| Teacher Physical Activity Behaviors | 4 weeks post intervention | Teacher physical activity will be measured via self-report of physical activity. |
Countries
United States
Participant flow
Recruitment details
68 preschools were screened
Pre-assignment details
51 preschools were randomized; 3 withdrew before baseline data collection. All students in a preschool were assigned to the same group. The study used an open cohort design in which all students who provided data at baseline and/or follow-up were included. Note: We use the 1136 preschool children included in the primary outcome (BMI z-score)
Participants by arm
| Arm | Count |
|---|---|
| Intervention Preschools participated in the A-B-C Healthy Me/Soy Saludable multi-component nutrition and physical activity preschool intervention. | 601 |
| Intervention Preschools participated in the A-B-C Healthy Me/Soy Saludable multi-component nutrition and physical activity preschool intervention. | 25 |
| Control Preschools continued with usual care practices. Control group preschools received intervention materials and accompanying instructions after follow-up measures were collected for each cohort. | 501 |
| Control Preschools continued with usual care practices. Control group preschools received intervention materials and accompanying instructions after follow-up measures were collected for each cohort. | 22 |
| Total | 1,149 |
Baseline characteristics
| Characteristic | Intervention | Total | Control |
|---|---|---|---|
| Age, Customized Age, Continuous | 45.3 Months STANDARD_DEVIATION 9.2 | 44.6 Months STANDARD_DEVIATION 9.4 | 43.7 Months STANDARD_DEVIATION 9.6 |
| Ethnicity (NIH/OMB) Hispanic or Latino | 237 Participants | 432 Participants | 195 Participants |
| Ethnicity (NIH/OMB) Not Hispanic or Latino | 195 Participants | 373 Participants | 178 Participants |
| Ethnicity (NIH/OMB) Unknown or Not Reported | 169 Participants | 297 Participants | 128 Participants |
| Race (NIH/OMB) American Indian or Alaska Native | 3 Participants | 3 Participants | 0 Participants |
| Race (NIH/OMB) Asian | 22 Participants | 40 Participants | 18 Participants |
| Race (NIH/OMB) Black or African American | 18 Participants | 40 Participants | 22 Participants |
| Race (NIH/OMB) More than one race | 121 Participants | 215 Participants | 94 Participants |
| Race (NIH/OMB) Native Hawaiian or Other Pacific Islander | 1 Participants | 1 Participants | 0 Participants |
| Race (NIH/OMB) Unknown or Not Reported | 340 Participants | 616 Participants | 276 Participants |
| Race (NIH/OMB) White | 96 Participants | 187 Participants | 91 Participants |
| Region of Enrollment United States | 601 participants | 1102 participants | 501 participants |
| Sex: Female, Male Female | 289 Participants | 513 Participants | 224 Participants |
| Sex: Female, Male Male | 312 Participants | 589 Participants | 277 Participants |
Adverse events
| Event type | EG000 affected / at risk | EG001 affected / at risk |
|---|---|---|
| deaths Total, all-cause mortality | 0 / 618 | 0 / 518 |
| other Total, other adverse events | 0 / 618 | 0 / 518 |
| serious Total, serious adverse events | 0 / 618 | 0 / 518 |
Outcome results
Primary
Child BMI Z-score
Height and weight of preschool children were measured by trained research staff. These data were used to calculate children's body mass index (BMI) scores. The BMI Z-score is a measure calculated from a child's height and weight that indicates how a child's BMI compares with the BMI of a reference population of U.S. children of the same age and sex. The reference population is based on Center for Disease Control and Prevention (CDC) pediatric growth charts and the BMI Z-score is calculated using a CDC-provided computer program. A Z-score of 0 corresponds to the mean BMI of the reference population. A Z-score of +1 corresponds to a BMI that is one standard deviation above the mean of the reference population, and a Z-score of -1 represents a BMI that is one standard deviation below the mean of the reference population. When used as a measure of obesity risk, a lower Z-score is considered a better outcome.
Time frame: Measured pre-intervention at the beginning of the school year and post-intervention at the end of the school year (approximately 10 months later)
Population: All participants for whom valid height, weight, age, and sex were collected at baseline and/or follow-up.
| Arm | Measure | Group | Value (MEAN) | Dispersion |
|---|---|---|---|---|
| Intervention | Child BMI Z-score | Follow-up | 0.31 Z-score | Standard Deviation 1.14 |
| Intervention | Child BMI Z-score | Baseline | 0.40 Z-score | Standard Deviation 1.07 |
| Control | Child BMI Z-score | Baseline | 0.43 Z-score | Standard Deviation 1.13 |
| Control | Child BMI Z-score | Follow-up | 0.48 Z-score | Standard Deviation 1.17 |
p-value: 0.00395% CI: [-0.31, -0.06]Mixed Models Analysis
Secondary
Frequency of Physical Activity
Parents completed surveys regarding children's physical activity and nutrition. For frequency of physical activity, the following question was asked: During the past 7 days, on how many days was your child physically active for a total of at least 60 minutes per day?
Time frame: Measured pre-intervention at the beginning of the school year and post-intervention at the end of the school year (approximately 10 months later)
Population: All participants with a valid response to the survey question of interest at baseline and/or follow-up.
| Arm | Measure | Group | Value (MEAN) | Dispersion |
|---|---|---|---|---|
| Intervention | Frequency of Physical Activity | Baseline | 4.9 days | Standard Deviation 2.1 |
| Intervention | Frequency of Physical Activity | Follow-up | 5.2 days | Standard Deviation 2 |
| Control | Frequency of Physical Activity | Baseline | 4.8 days | Standard Deviation 2.1 |
| Control | Frequency of Physical Activity | Follow-up | 5.4 days | Standard Deviation 2 |
p-value: 0.395% CI: [-0.58, 0.17]Mixed Models Analysis
Secondary
Nutrition and Physical Activity Policies and Practices at Preschool Site Level
Nutrition and physical activity policies of the preschool will be assessed via in-person all day observations of one preschool classroom per site. Trained research staff will conduct these observations during an on-site visit to the center. Additionally, preschool site directors will complete a nutrition and physical activity policy and practice survey to assess center nutrition and physical activity policies.
Time frame: 4 weeks post intervention
Secondary
Percentage of Children Who Eat Fruit Once a Day
Parents completed surveys regarding children's physical activity and nutrition. For frequency of fruit consumption, the following question was asked: How often does your child eat... fruit? Include fresh, frozen, or canned fruit. DO NOT include juices. The response is dichotomized as at least once a day versus less than once a day.
Time frame: Measured pre-intervention at the beginning of the school year and post-intervention at the end of the school year (approximately 10 months later)
Population: All participants with a valid response to the survey question at baseline and/or follow-up.
| Arm | Measure | Group | Value (NUMBER) |
|---|---|---|---|
| Intervention | Percentage of Children Who Eat Fruit Once a Day | Baseline | 82 Percent of children who eat fruits |
| Intervention | Percentage of Children Who Eat Fruit Once a Day | Follow-up | 86 Percent of children who eat fruits |
| Control | Percentage of Children Who Eat Fruit Once a Day | Baseline | 76 Percent of children who eat fruits |
| Control | Percentage of Children Who Eat Fruit Once a Day | Follow-up | 82 Percent of children who eat fruits |
p-value: 0.795% CI: [0.034, 4.91]Mixed Models Analysis
Secondary
Percentage of Children Who Eat Vegetables Once a Day
Parents completed surveys regarding children's physical activity and nutrition. For frequency of vegetable consumption, the following question was asked: How often does your child eat... vegetables? DO NOT count potatoes, or beans. The response is dichotomized as at least once a day versus less than once a day.
Time frame: Measured pre-intervention at the beginning of the school year and post-intervention at the end of the school year (approximately 10 months later)
Population: All participants with a valid response to the survey question at baseline and/or follow-up.
| Arm | Measure | Group | Value (NUMBER) |
|---|---|---|---|
| Intervention | Percentage of Children Who Eat Vegetables Once a Day | Baseline | 61 Percentage children who eat vegetables |
| Intervention | Percentage of Children Who Eat Vegetables Once a Day | Follow-up | 69 Percentage children who eat vegetables |
| Control | Percentage of Children Who Eat Vegetables Once a Day | Baseline | 61 Percentage children who eat vegetables |
| Control | Percentage of Children Who Eat Vegetables Once a Day | Follow-up | 69 Percentage children who eat vegetables |
p-value: 0.895% CI: [0.56, 2.16]Mixed Models Analysis
p-value: 0.895% CI: [0.56, 2.16]Mixed Models Analysis
Secondary
Teacher Nutrition Behaviors
Teacher nutrition will be measured via self-report of dietary intake.
Time frame: 4 weeks post intervention
Secondary
Teacher Physical Activity Behaviors
Teacher physical activity will be measured via self-report of physical activity.
Time frame: 4 weeks post intervention