Mode of Collection:
Mail survey, with telephone follow-up for nonrespondents.
PRAMS data include basic demographic information, barriers to and content of prenatal care, obstetric history, maternal use of alcohol and cigarettes, maternal stress, and early infant development and health status.
Mothers and infants in participating states.
The PRAMS sample of women who have had a recent live birth is drawn from the state's birth certificate file. Each participating state draws a sample of 100 to 250 new mothers every month from a frame of eligible birth certificates. Most states oversample low birth weights; many states stratify by mother's race or ethnicity as well. Annual sample sizes range from 1,300 to 3,400, divided among 3 to 6 strata. Selected women are contacted by mail 2 to 4 months after delivery. Repeated attempts are made to contact nonrespondents to obtain cooperation. Mothers' responses are linked to extracted birth certificate data items for analysis. The birth certificate file is the basis for generalizing results to the entire population and for deriving nonresponse rates.
Response Rates and Sample Size:
The number of states participating in PRAMS varies by year. In 2008, 23 states participated. State sample sizes range from 1,300 to 3,400. States with a response rate below 65% (70% prior to 2006) are not included in the PRAMS analysis files.