"Greenlight study": a controlled trial of low-literacy, early childhood obesity prevention

Abstract

Children who become overweight by age 2 years have significantly greater risks of long-term health problems, and children in low-income communities, where rates of low adult literacy are highest, are at increased risk of developing obesity. The objective of the Greenlight Intervention Study is to assess the effectiveness of a low-literacy, primary-care intervention on the reduction of early childhood obesity. At 4 primary-care pediatric residency training sites across the US, 865 infant-parent dyads were enrolled at the 2-month well-child checkup and are being followed through the 24-month well-child checkup. Two sites were randomly assigned to the intervention, and the other sites were assigned to an attention-control arm, implementing the American Academy of Pediatrics' The Injury Prevention Program. The intervention consists of an interactive educational toolkit, including low-literacy materials designed for use during well-child visits, and a clinician-centered curriculum for providing low-literacy guidance on obesity prevention. The study is powered to detect a 10% difference in the number of children overweight (BMI > 85%) at 24 months. Other outcome measures include observed physician-parent communication, as well as parent-reported information on child dietary intake, physical activity, and injury-prevention behaviors. The study is designed to inform evidence-based standards for early childhood obesity prevention, and more generally to inform optimal approaches for low-literacy messages and health literacy training in primary preventive care. This article describes the conceptual model, study design, intervention content, and baseline characteristics of the study population.

Trial registration: ClinicalTrials.gov NCT01040897.

Keywords: early childhood; health literacy; injury prevention; obesity prevention; primary care; resident education.

FIGURE 1

Conceptual model, relating parent health literacy to child health outcomes (from Sanders LM, Shaw JS, Guez G, Baur C, Rudd R. Health literacy and child health promotion: implications for research, clinical care and public policy. Pediatrics. 2009;124:S306–S314).

FIGURE 2

Sample core booklet (pages 1, 4, 5, and 12 from 12-month booklet).

FIGURE 3

Sample supplementary booklet (pages 1 and 4 from “Active Time” Supplement, for all ages).

FIGURE 4

A, Tangible tool given at 2 months of age: t-shirt. B, Tangible tool given at 9 months of age: sippy cup. C, Tangible tool given at 12 months of age: portion-size bowls, with birthday card. D, Tangible tool given at 15 to 18 months of age: placemat showing portion sizes.

FIGURE 5

Observation checklist.

FIGURE 6

Study flow.