Survey methodology of the geographic research on wellbeing (GROW) study

BACKGROUND: Causal inferences from survey research on health would benefit from population-based prospective survey designs. Because of decreasing survey response rates and residential mobility, however, loss to follow-up is of concern. The purpose of this paper is to describe the methodology of the geographic research on wellbeing (GROW) study and the resulting sample of women, their children, and their neighborhoods. RESULTS: GROW (2012–2013) was designed as a follow-up mail/telephone survey of postpartum women who completed the statewide-representative Maternal and Infant Health Assessment (MIHA) baseline survey (2003–2007) in California. GROW was completed in English or Spanish by mothers whose index child from MIHA were aged 4–10 years. Its research focus is on the role of neighborhood environments on behavioral risk factors for cancer. The survey was developed based on expert guidance and extensive pilot testing and includes in-depth information on women’s and children’s health and behaviors, socioeconomic and demographic factors, psychosocial characteristics, and neighborhood perceptions, linked to objective neighborhood characteristics. The sample size for GROW is 3016 women. Response rates were 33 % of the eligible sample and 75 % of the active sample (those able to be located). GROW appears to be highly representative of its target population and its respondents lived in similar types of neighborhoods compared with all California neighborhoods. DISCUSSION: Surveyed 5–10 years after baseline, the GROW mixed-mode methodology produced a prospective, representative sample of women with young children in California, comparing both individual and residential characteristics. The methods have implications for the 40 states and New York City that participate in CDC’s Pregnancy Risk Assessment Monitoring System, as well as other cross-sectional studies with participants’ contact information. Several recommendations for conducting similar follow-up studies with minimal loss to follow-up are provided.