The Pregnancy Risk Assessment Monitoring System (PRAMS): current methods and evaluation of 2001 response rates

Our objectives were to describe the methodology of the Pregnancy Risk Assessment Monitoring System (PRAMS), examine recent response rates, determine characteristics associated with response, and track response patterns over time.

PRAMS is a mixed-mode surveillance system, using mail and telephone surveys. Rates for response, contact, cooperation, and refusal were computed for 2001. Logistic regression was used to examine the relationship between maternal and infant characteristics and the likelihood of response. Response patterns from 1996 to 2001 were compared for nine states.

The median response rate for the 23 states in 2001 was 76% (range: 49% to 84%). Cooperation rates ranged from 86% to 97% (median 91%); contact rates ranged from 58% to 93% (median 82%). Response rates were higher for women who were older, white, married, had more education, were first-time mothers, received early prenatal care, and had a normal birthweight infant. Education level was the most consistent predictor of response, followed by marital status and maternal race. From 1996 to 2001, response to the initial mailing decreased in all states compared, but the decrease was offset by increases in mail follow-up and telephone response rates. Overall response rates remained unchanged.

The PRAMS mail/telephone methodology is an effective means of reaching most recent mothers in the 23 states examined, but some population subgroups are more difficult to reach than others. Through more intensive follow-up efforts, PRAMS states have been able to maintain high response rates over time despite decreases in response to the initial mailing.