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2011 Survey Results

Pregnancy Risk Assessment Monitoring System (PRAMS)

2011 PRAMS Technical Notes

Detailed data tables for NC PRAMS survey items are posted on an annual basis. Wording from each question is used as a title for most survey items; however, due to space limitations, titles may not include introductory remarks and explanations for some questions. For further information on survey questions, refer to the corresponding annual questionnaires. Some questions from the survey are not presented in the web tables due to a small number of respondents for that question.

Estimates are available for survey items tabulated by characteristics of the respondent, including maternal age, race/ethnicity, education, marital status, WIC enrollment, Medicaid participation, and the infant’s birth weight. County-level estimates are not reported due to the small sample size of the PRAMS survey.

Interpreting Results

Percentages shown in NC PRAMS data tables are calculated using weighted data and therefore cannot be derived exactly from the counts in the tables. Weighting adjusts for unequal probabilities of selection due to the disproportionate sampling method used for PRAMS.

Respondents who refused to answer or did not know the answer were excluded from most calculations in these tables. However, there are instances when "Don't know/Not sure" responses may provide valuable information and are included in the response categories.

NC PRAMS data tables present the 95 percent confidence interval (C.I.) associated with each estimate, or percent, reported in the tables. Since the NC PRAMS Survey it is not a simple random sample, the State Center for Health Statistics uses SUDAAN software to calculate the point estimates and confidence intervals. This software takes into account the complex sampling design, when computing the variance, or sampling error, associated with the estimates. The 95 percent confidence interval indicates the range in which the true population value would occur 95 out of 100 times, if 100 different random samples were taken of the population.

The primary goal of SCHS is to provide high quality health information for better informed decisions and effective health policies. Consistent with this goal, we have suppressed prevalence estimates which did not met minimal criteria for statistical reliability based on sample size, the width of the confidence intervals and the relative standard error (RSE). The relative standard error (RSE), also known as the coefficient of variation (CV), is a measure of the variability of the estimate compared with the magnitude of the estimate. It may be thought of as the percentage of the estimate that is subject to random error. The RSE describes the variability in a set of measurements by expressing the standard deviation or standard error as a percentage of the estimate.

PRAMS prevalence estimates were suppressed when any of the following criteria were met:

  • There were fewer than 10 respondents in the numerator (i.e. the number of respondents associated with the response categories, e.g. “Yes”, “No”).
  • The relative standard error (RSE) is greater than .30, indicating that more than 30 percent of the size of the estimate may be due to random error.

For additional information regarding NC PRAMS, please contact the NC PRAMS Staff.