title: A pooled analysis of extremely low-frequency magnetic fields and childhood brain tumors.
abstract: Pooled analyses may provide etiologic insight about associations between exposure and disease. In contrast to childhood leukemia, no pooled analyses of childhood brain tumors and exposure to extremely low-frequency magnetic fields (ELF-MFs) have been conducted. The authors carried out a pooled analysis based on primary data (1960-2001) from 10 studies of ELF-MF exposure and childhood brain tumors to assess whether the combined results, adjusted for potential confounding, indicated an association. The odds ratios for childhood brain tumors in ELF-MF exposure categories of 0.1-<0.2 μT, 0.2-<0.4 μT, and ≥0.4 μT were 0.95 (95% confidence interval: 0.65, 1.41), 0.70 (95% CI: 0.40, 1.22), and 1.14 (95% CI: 0.61, 2.13), respectively, in comparison with exposure of <0.1 μT. Other analyses employing alternate cutpoints, further adjustment for confounders, exclusion of particular studies, stratification by type of measurement or type of residence, and a nonparametric estimate of the exposure-response relation did not reveal consistent evidence of increased childhood brain tumor risk associated with ELF-MF exposure. These results provide little evidence for an association between ELF-MF exposure and childhood brain tumors.
authors.affiliation: Department of Epidemiology, School of Public Health, University of California, Los Angeles, Los Angeles, California 90095-1772, USA. kheifets@ucla.edu
authors.forename: Leeka
authors.initials: L
authors.lastname: Kheifets
authors.forename: A
authors.initials: A
authors.lastname: Ahlbom
authors.forename: C M
authors.initials: CM
authors.lastname: Crespi
authors.forename: M
authors.initials: M
authors.lastname: Feychting
authors.forename: C
authors.initials: C
authors.lastname: Johansen
authors.forename: J
authors.initials: J
authors.lastname: Monroe
authors.forename: M F G
authors.initials: MF
authors.lastname: Murphy
authors.forename: S
authors.initials: S
authors.lastname: Oksuzyan
authors.forename: S
authors.initials: S
authors.lastname: Preston-Martin
authors.forename: E
authors.initials: E
authors.lastname: Roman
authors.forename: T
authors.initials: T
authors.lastname: Saito
authors.forename: D
authors.initials: D
authors.lastname: Savitz
authors.forename: J
authors.initials: J
authors.lastname: Schüz
authors.forename: J
authors.initials: J
authors.lastname: Simpson
authors.forename: J
authors.initials: J
authors.lastname: Swanson
authors.forename: T
authors.initials: T
authors.lastname: Tynes
authors.forename: P
authors.initials: P
authors.lastname: Verkasalo
authors.forename: G
authors.initials: G
authors.lastname: Mezei
mesh_terms: D001932:Brain Neoplasms / Q000453:epidemiology / Q000209:etiology*; D002648:Child; D004574:Electromagnetic Fields / Q000009:adverse effects*; D014943:Global Health; D006801:Humans; D015994:Incidence; D009381:Neoplasms, Radiation-Induced / Q000453:epidemiology*; D012307:Risk Factors