title: Magnetic fields exposure and childhood leukemia risk: a meta-analysis based on 11,699 cases and 13,194 controls.
abstract: OBJECTIVE
  To observe the association between childhood leukemia and magnetic field exposure.
  
  
  METHODS
  The literature was searched by PubMed, ProQuest, Web of Science (SCI) and Medline databases during 1997-2013. Heterogeneity in several studies was weighted by I-squared value. Publication bias was tested by funnel plot and Egger's test. Odds ratio (OR) and 95% CI were used to evaluate the association strength. The statistical analyses in present study were carried out by STATA software package (version 12.0, College Station, TX).
  
  
  RESULTS
  A total of 11,699 cases and 13,194 controls in 9 studies were stratified by different exposure cut-off points. On condition of the reference <0.1 μT, statistical association between magnetic field intensity ≥0.4 μT and childhood leukemia was exhibited (for total leukemia: OR = 1.57, 95% CI = 1.03-2.40; for acute lymphocytic leukemia: OR=2.43, 95% CI = 1.30-4.55). On condition of the reference level of <0.2 μT, the positive association between magnetic field intensity ≥0.2 μT and childhood leukemia was found (OR = 1.31, 95% CI = 1.06-1.61).
  
  
  CONCLUSIONS
  The result in this meta-analysis indicated that magnetic field exposure level may be associated with childhood leukemia.
authors.affiliation: Epidemiology and Statistics, School of Public Health, Jilin University, Changchun, Jilin, China.
authors.forename: Longyu
authors.initials: L
authors.lastname: Zhao
authors.affiliation: Key Laboratory of Radiobiology (Ministry of Health), School of Public Health, Jilin University, Changchun, China.
authors.forename: Xiaodong
authors.initials: X
authors.lastname: Liu
authors.affiliation: School of Mathematics and Statistics, Northeast Normal University, Changchun, Jilin, China.
authors.forename: Chunpeng
authors.initials: C
authors.lastname: Wang
authors.affiliation: Epidemiology and Statistics, School of Public Health, Jilin University, Changchun, Jilin, China.
authors.forename: Kangkang
authors.initials: K
authors.lastname: Yan
authors.affiliation: Epidemiology and Statistics, School of Public Health, Jilin University, Changchun, Jilin, China.
authors.forename: Xuejun
authors.initials: X
authors.lastname: Lin
authors.affiliation: Epidemiology and Statistics, School of Public Health, Jilin University, Changchun, Jilin, China.
authors.forename: Shuang
authors.initials: S
authors.lastname: Li
authors.affiliation: Epidemiology and Statistics, School of Public Health, Jilin University, Changchun, Jilin, China.
authors.forename: Honghong
authors.initials: H
authors.lastname: Bao
authors.affiliation: Epidemiology and Statistics, School of Public Health, Jilin University, Changchun, Jilin, China. Electronic address: xliu@jlu.edu.cn.
authors.forename: Xin
authors.initials: X
authors.lastname: Liu
mesh_terms: D000293:Adolescent; D016022:Case-Control Studies; D002648:Child; D002675:Child, Preschool; D016206:Databases, Bibliographic; D005260:Female; D006801:Humans; D060526:Magnetic Fields / Q000009:adverse effects*; D008297:Male; D016017:Odds Ratio; D054198:Precursor Cell Lymphoblastic Leukemia-Lymphoma / Q000453:epidemiology / Q000209:etiology* / Q000473:pathology
keywords: Childhood; Leukemia; Magnetic field; Meta-analysis; Risk