PRAMS Data Collection Methodology

One of the strengths of PRAMS is that each participating state uses a standardized data collection methodology. This standardized approach allows for comparisons among states and for optimal use of the data for single-state or multistate analysis. Each state follows the standardized data collection methodology but can also customize some portions of it to tailor the procedures to the needs of the state. PRAMS is a mixed-mode surveillance system that combines two modes of data collection. Each month, a stratified sample is drawn from the current birth certificate file.

For each of these monthly samples, or "batches," a sequence of mail and telephone contacts is attempted. CDC developed and installed a customized tracking system, PRAMTrac, in each state to assist with scheduling mailings and telephone calls, preparing letters, and tracking responses. The primary data collection method is a mail survey. Up to three self-administered surveys are mailed to sampled women, and then mail nonrespondents are contacted by telephone. Here is the sequence of contacts for PRAMS surveillance:

  1. Preletter. This letter introduces PRAMS to the sampled mother and informs her that a questionnaire will soon arrive.
  2. Initial Mail Questionnaire Packet. This packet is sent to all sampled mothers 3 to 7 days after the preletter.
  3. Tickler. The tickler serves as a thank you/reminder note. It is sent 7 to 10 days after the initial mail packet.
  4. Second Mail Questionnaire Packet. This packet is sent 7 to 14 days after the tickler to all sampled mothers who did not respond.
  5. Third Mail Questionnaire Packet. This third packet is sent to all remaining nonrespondents 7 to 14 days after the second questionnaire was sent.
  6. Telephone Follow-Up. Telephone follow up is initiated for all nonrespondents 7 to 14 days after the mailing of the last questionnaire.

The series of mailings commences 2 to 6 months after the mother delivers her infant. Most mothers respond within 3 to 5 months after giving birth. The questionnaire contains items asking about the early postpartum period; thus, the mailings are timed to ensure that all women can respond for this period. The data collection cycle from the mailing of the preletter to the close of telephone follow up lasts approximately 65 to 85 days. The mail questionnaire packet contains several items.

Telephone follow-up begins after the mailing of the last questionnaire. A variety of sources of telephone numbers are used to obtain a valid number for a mother. Calls to a particular number are staggered over different times of the day and different days of the week. The calling period for a batch runs 2 to 3 weeks. Up to 15 call attempts are made to a number in order to reach a mother. Often, telephone interviewers arrange call-back interviews to accommodate the mother’s schedule. Starting in 2005, all states use standardized web-based CATI (Computer Assisted Telephone Interviewing) software for telephone follow-up