The PRAMS sample of women who have had a recent live birth is drawn from the state's birth certificate file. Iowa samples about 1,800 women per year. Women from some groups are sampled at a higher rate to ensure adequate data are available in smaller but higher risk populations.
Selected women are first contacted by mail. If there is no response to repeated mailings, women are contacted and interviewed by telephone. Women who complete the survey (either by mail or phone) are mailed a $10 gift certificate for diapers.
Data collection procedures and instruments are standardized to allow comparisons between states.