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:
- Preletter. This letter introduces PRAMS to the sampled mother and
informs her that a questionnaire will soon arrive.
- Initial Mail Questionnaire Packet. This packet is sent to all sampled
mothers 3 to 7 days after the preletter.
- Tickler. The tickler serves as a thank you/reminder note. It is sent
7 to 10 days after the initial mail packet.
- Second Mail Questionnaire Packet. This packet is sent 7 to 14 days
after the tickler to all sampled mothers who did not respond.
- Third Mail Questionnaire Packet. This third packet is sent to all
remaining nonrespondents 7 to 14 days after the second questionnaire was
- 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 motherís schedule.
Starting in 2005, all states use standardized web-based CATI (Computer
Assisted Telephone Interviewing) software for telephone follow-up