Evidence of localized clustering of gastroschisis births in North Carolina, 1999-2004

Elisabeth D. Root, University of Colorado at Boulder
Robert Meyer, University of North Carolina at Chapel Hill
Michael Emch, University of North Carolina at Chapel Hill

Identification of clusters of poor birth outcomes may uncover possible socio-economic or environmental risk factors and assist with the generation of hypotheses about underlying causes of these conditions. Around the world, the prevalence of gastroschisis, a serious abdominal wall defect, has increased over the past decade. This study uses a spatial scan statistic to identify the location and extent of clusters of gastroschisis births in North Carolina between 1999 and 2004. The clusters were controlled for four major risk factors (age, race, parity and primary insurer) to ensure that clusters were not an artifact of unequal population distribution. Results indicate a localized cluster of gastroschisis in the rural southern Piedmont of North Carolina which persists even after controlling for all major risk factors. Adjusting for age, race, parity and primary insurer shifted the location of the cluster substantially, demonstrating the importance of adjusting for underlying population distribution.