On the following pages, birth defects surveillance data are presented for 35 states. In this issue, state surveillance programs were requested to provide birth defects data for the time period January 1, 1996 through December 31, 2000. This presentation, showing the most current five-year data totals available, follows the 2002 report (NBDPN, '02) rather than include more historical data as in previous reports (NBDPN, '97, '00, '01). Differences in surveillance methodology among states preclude the ability to provide rates for all programs combined.
State programs were asked to provide surveillance data on 45 specific birth defects as detailed in Appendix A on page 822. Programs were asked to identify the occurrence of each specific defect for all live births, stillbirths and terminations (if collected), and data submitted were to be stratified by race/ethnic group and, for certain defects (trisomy 13, 18 and 21), by maternal age. To calculate rates, programs were asked to provide data on the number of live births for each calendar year requested.
Although an attempt was made to standardize both the request and presentation of state surveillance data, differences in the way programs collect and report birth defects data are listed in the footnotes in the accompanying tables and may be referenced in the program directories on pages 670-728. Along with the inability of some programs to provide data for each of the years included in the report, others varied in their ability to report counts and rates by race/ethnicity, and still others were unable either to provide data for each specific defect requested due to differences in the coding systems (i.e., ICD-9-CM vs. CDC/BPA) used to classify birth defects.
In the previous report, graphs displaying annual rates for neural tube defects (spina bifida and anencephaly) were included to highlight the trend in occurrence of these defects over a five-year period. This year's report focuses on the prevalence rates of fetal alcohol syndrome and compares the case ascertainment methodologies used by the Fetal Alcohol Syndrome Surveillance Network (FASS-Net) and state birth defects surveillance programs. Prevalence data are presented by race/ethnicity for the period 1995-1999. For a more detailed presentation of other birth defects, the reader is encouraged to visit the NBDPN web site at www.nbdpn.org/NBDPN.