title: Spatial distribution patterns of anorectal atresia/stenosis in China: use of two-dimensional graph-theoretical clustering.
abstract: OBJECTIVE
  To investigate the spatial distribution patterns of anorectal atresia/stenosis in China.
  
  
  METHODS
  Data were collected from the Chinese Birth Defects Monitoring Network (CBDMN), a hospital-based congenital malformations registry system. All fetuses more than 28 wk of gestation and neonates up to 7 d of age in hospitals within the monitoring sites of the CBDMN were monitored from 2001 to 2005. Two-dimensional graph-theoretical clustering was used to divide monitoring sites of the CBDMN into different clusters according to the average incidences of anorectal atresia/stenosis in the different monitoring sites.
  
  
  RESULTS
  The overall average incidence of anorectal atresia/stenosis in China was 3.17 per 10,000 from 2001 to 2005. The areas with the highest average incidences of anorectal atresia/stenosis were almost always focused in Eastern China. The monitoring sites were grouped into 6 clusters of areas. Cluster 1 comprised the monitoring sites in Heilongjiang Province, Jilin Province, and Liaoning Province; Cluster 2 was composed of those in Fujian Province, Guangdong Province, Hainan Province, Guangxi Zhuang Autonomous Region, south Hunan Province, and south Jiangxi Province; Cluster 3 consisted of those in Beijing Municipal City, Tianjin Municipal City, Hebei Province, Shandong Province, north Jiangsu Province, and north Anhui Province; Cluster 4 was made up of those in Zhejiang Province, Shanghai Municipal City, south Anhui Province, south Jiangsu Province, north Hunan Province, north Jiangxi Province, Hubei Province, Henan Province, Shanxi Province and Inner Mongolia Autonomous Region; Cluster 5 consisted of those in Ningxia Hui Autonomous Region, Gansu Province and Qinghai Province; and Cluster 6 included those in Shaanxi Province, Sichuan Province, Chongqing Municipal City, Yunnan Province, Guizhou Province, Xinjiang Uygur Autonomous Province and Tibet Autonomous Region.
  
  
  CONCLUSIONS
  The findings in this research allow the display of the spatial distribution patterns of anorectal atresia/stenosis in China. These will have important guiding significance for further analysis of relevant environmental factors regarding anorectal atresia/stenosis and for achieving regional monitoring for anorectal atresia/stenosis.
authors.affiliation: National Center for Birth Defects Monitoring, West China Second University Hospital, Sichuan University, Chengdu, Sichuan Province, China.
authors.forename: Ping
authors.initials: P
authors.lastname: Yuan
authors.forename: Liang
authors.initials: L
authors.lastname: Qiao
authors.forename: Li
authors.initials: L
authors.lastname: Dai
authors.forename: Yan-Ping
authors.initials: YP
authors.lastname: Wang
authors.forename: Guang-Xuan
authors.initials: GX
authors.lastname: Zhou
authors.forename: Ying
authors.initials: Y
authors.lastname: Han
authors.forename: Xiao-Xia
authors.initials: XX
authors.lastname: Liu
authors.forename: Xun
authors.initials: X
authors.lastname: Zhang
authors.forename: Yi
authors.initials: Y
authors.lastname: Cao
authors.forename: Juan
authors.initials: J
authors.lastname: Liang
authors.forename: Jun
authors.initials: J
authors.lastname: Zhu
mesh_terms: D001006:Anus, Imperforate / Q000453:epidemiology* / Q000473:pathology; D002681:China / Q000453:epidemiology; D016000:Cluster Analysis; D003251:Constriction, Pathologic / Q000151:congenital / Q000453:epidemiology; D005260:Female; D005333:Fetus / Q000002:abnormalities; D005865:Gestational Age; D006801:Humans; D007231:Infant, Newborn; D008962:Models, Theoretical; D011247:Pregnancy; D012007:Rectum / Q000002:abnormalities*; D012042:Registries