Míranos! Program, a Preschool Obesity Prevention RCT

Using a three-arm design, 12 Head Start (HS) centers in equal number will be randomly
assigned to one of three conditions: 1) a combined center- and home-based intervention, 2)
center-based intervention only, or 3) active control. The interventions will be delivered
during the academic year (an 8-month [mo] period). A total of 525 3-year-old children (52%
females; in two cohorts) will be enrolled in the study at baseline and followed prospectively
one-year post-intervention. The first cohort will be recruited in summer 2018. The second
cohort will be recruited in summer 2019.

Data collection will be conducted at baseline (T0), immediate post-intervention (T1), and
1-year post-intervention follow-up (T2) and include children's height, weight,
accelerometry-based PA and sedentary behavior, TV watching and sleep by parent reports, gross
motor development, dietary intakes, food preference. Information on family background,
parental PA- and nutrition-related practices, parental weight and health behaviors, PA and
nutrition policies and environments at the center and home, and costs associated with
intervention delivery will be collected. The primary endpoint for the study is the BMI at the
posttest immediately following the completion of the intervention (T1).

Recruitment: Participant recruitment will take place during summer by sending a recruitment
packet to child's home. This packet includes: study information sheet, recruitment flyer,
informed consent form, a letter from center director and study PIs.

Process Evaluation: The process evaluation is informed by the NIH Behavior Change Consortium
Treatment Fidelity Workgroup's best practice recommendations and recent multi-component RCTs.
Míranos! has multiple components with multiple activities, the investigators will use many
indicators to evaluate the fidelity and completeness of the implementation of all components
and determine contribution of each component by linking it to the primary and secondary
outcomes. The investigators will collect both quantitative/qualitative data to assess
cross-site treatment consistency, non-treatment-related effects, and document protocol
changes.

First, intervention dose delivered will be measured by: 1) pre-/post-study center
environmental assessment by the Environment and Policy Assessment and Observations (EPAO) and
auditing of meal menus; 2) completion of delivery schedule of staff, peer leader training,
parent education sessions, home visits; 3) evaluation of staff, peer leader training; 4)
monthly auditing of weekly lesson plans; and 5) monthly checklist of use of Míranos! Activity
Cards, children's story books, HHL learning activities.

Second, the intervention dose received will be assessed by: 1) attendance records of staff,
peer leader training, parent education sessions; 2) certification test of staff, peer leader
training; 3) monthly staff evaluation (rating scale) of children's learning of HHL content,
gross motor skills, eating behaviors; 4) post-study parent intercept interviews; and 5)
post-study focus groups on program delivery process with staff (n=24) and parents (n=32).

Third, participants' responses to the intervention will be evaluated by: 1) random
observations of staff behavior (rating scale) during outdoor play and lunch by research
staff; 2) assessments on children's PA by the System for Observing Fitness Instruction Time
for Preschoolers and diet by group plate waste test in 3 randomly selected centers; 3)
in-depth interviews with staff (n=48) for program feedback; and 4) post-study staff and
parent evaluation (rating scale) of satisfaction with intervention components/activities.

Inclusion Criteria:

- The child must be enrolled in a full-day Head Start center

- The child must be 3 years old at baseline, one child per family, parental consent

Exclusion Criteria: