Stanford GEMS phase 2 obesity prevention trial for low-income African-American girls: design and sample baseline characteristics

Contemp Clin Trials. 2008 Jan;29(1):56-69. doi: 10.1016/j.cct.2007.04.007. Epub 2007 May 25.


Objective: African-American girls and women are at high risk of obesity and its associated morbidities. Few studies have tested obesity prevention strategies specifically designed for African-American girls. This report describes the design and baseline findings of the Stanford GEMS (Girls health Enrichment Multi-site Studies) trial to test the effect of a two-year community- and family-based intervention to reduce weight gain in low-income, pre-adolescent African-American girls.

Design: Randomized controlled trial with measurements scheduled in girls' homes at baseline, 6, 12, 18 and 24 month post-randomization.

Setting: Low-income areas of Oakland, CA.

Participants: Eight, nine and ten year old African-American girls and their parents/caregivers.

Interventions: Girls are randomized to a culturally-tailored after-school dance program and a home/family-based intervention to reduce screen media use versus an information-based community health education Active-Placebo Comparison intervention. Interventions last for 2 years for each participant.

Main outcome measure: Change in body mass index over the two-year study.

Results: Recruitment and enrollment successfully produced a predominately low-socioeconomic status sample. Two-hundred sixty one (261) families were randomized. One girl per family is randomly chosen for the analysis sample. Randomization produced comparable experimental groups with only a few statistically significant differences. The sample had a mean body mass index (BMI) at the 74 th percentile on the 2000 CDC BMI reference, and one-third of the analysis sample had a BMI at the 95th percentile or above. Average fasting total cholesterol and LDL cholesterol were above NCEP thresholds for borderline high classifications. Girls averaged low levels of moderate to vigorous physical activity, more than 3 h per day of screen media use, and diets high in energy from fat.

Conclusions: The Stanford GEMS trial is testing the benefits of culturally-tailored after-school dance and screen-time reduction interventions for obesity prevention in low-income, pre-adolescent African-American girls.

Publication types

  • Randomized Controlled Trial

MeSH terms

  • African Americans*
  • Body Mass Index
  • Child
  • Cholesterol / blood
  • Diet
  • Female
  • Health Education / organization & administration*
  • Humans
  • Obesity / prevention & control*
  • Poverty*
  • Self Concept
  • Socioeconomic Factors


  • Cholesterol