Application of the automated spatial surveillance program to birth defects surveillance data.
BACKGROUND
Although many birth defects surveillance programs incorporate georeferenced records into their databases, practical methods for routine spatial surveillance are lacking. We present a macroprogram written for the software package R designed for routine exploratory spatial analysis of birth defects data, the Automated Spatial Surveillance Program (ASSP), and present an application of this program using spina bifida prevalence data for metropolitan Atlanta.


METHODS
Birth defects surveillance data were collected by the Metropolitan Atlanta Congenital Defects Program. We generated ASSP maps for two groups of years that correspond roughly to the periods before (1994-1998) and after (1999-2002) folic acid fortification of flour. ASSP maps display census tract-specific spina bifida prevalence, smoothed prevalence contours, and locations of statistically elevated prevalence. We used these maps to identify areas of elevated prevalence for spina bifida.


RESULTS
We identified a large area of potential concern in the years following fortification of grains and cereals with folic acid. This area overlapped census tracts containing large numbers of Hispanic residents.


CONCLUSIONS
The potential utility of ASSP for spatial disease monitoring was demonstrated by the identification of areas of high prevalence of spina bifida and may warrant further study and monitoring. We intend to further develop ASSP so that it becomes practical for routine spatial monitoring of birth defects.
Gardner
Bennett R
BR
National Center on Birth Defects and Developmental Disabilities, Centers for Disease Control and Prevention, Atlanta, Georgia 30333, USA.
Strickland
Matthew J
MJ
Correa
Adolfo
A
D001331:Automation; D000013:Congenital Abnormalities / Q000453:epidemiology*; D005260:Female; D005315:Fetal Diseases / Q000453:epidemiology; D005492:Folic Acid / Q000378:metabolism; D006801:Humans; D009436:Neural Tube Defects / Q000453:epidemiology; D011159:Population Surveillance; D011247:Pregnancy; D015995:Prevalence; D012984:Software; D016135:Spinal Dysraphism / Q000453:epidemiology; D013997:Time Factors
D005492:Folic Acid