title: [Relationship between reference values of fibrinogen and geographical factors based on neural network analysis].
abstract: OBJECTIVE
  To analyze the relationship between the reference values of fibrinogen (FIB) in healthy Chinese adults and geographical factors to provide scientific evidences for establishing the uniform standard.
  
  
  METHODS
  The reference values of FIB of 10701 Chinese healthy adults from 103 cities were collected to investigate their relationship with 18 geographical factors including spatial index, terrain index, climate index, and soil index. Geographical factors that significantly correlated with the reference values were selected for constructing the BP neural network model. The spatial distribution map of the reference value of FIB of healthy Chinese adults was fitted by disjunctive kriging interpolation. We used the 5-layer neural network and selected 2000 times of training covering 11 hidden layers to build the simulation rule for simulating the relationship between FIB and geographical environmental factors using the MATLAB software.
  
  
  RESULTS
  s The reference value of FIB in healthy Chinese adults was significantly correlated with the latitude, sunshine duration, annual average temperature, annual average relative humidity, annual precipitation, annual range of air temperature, average annual soil gravel content, and soil cation exchange capacity (silt). The artificial neural networks were created to analyze the simulation of the selected indicators of geographical factors. The spatial distribution map of the reference values of FIB in healthy Chinese adults showed a distribution pattern that FIB levels were higher in the South and lower in the North, and higher in the East and lower in the West.
  
  
  CONCLUSIONS
  When the geographical factors of a certain area are known, the reference values of FIB in healthy Chinese adults can be obtained by establishing the neural network mode or plotting the spatial distribution map.
authors: Institute of Health and Geography, College of Tourism and Environment, Shaanxi Normal University, Xi'an 710062, China. E-mail: maggie_322@163.com.
authors: Meng-Jiao
authors: MJ
authors: Li
authors: Miao
authors: M
authors: Ge
authors: Cong-Xia
authors: CX
authors: Wang
authors: Min-Yi
authors: MY
authors: Cen
authors: Ji-Lin
authors: JL
authors: Jiang
authors: Jin-Wei
authors: JW
authors: He
authors: Qian-Yi
authors: QY
authors: Lin
authors: Xin
authors: X
authors: Liu
mesh_terms: D000328:Adult; D044466:Asian People; D002681:China; D002980:Climate; D004777:Environment; D005340:Fibrinogen; D005843:Geography; D006801:Humans; D016571:Neural Networks, Computer; D012016:Reference Values; D012984:Software; D013696:Temperature
chemical_list: D005340:Fibrinogen