Meta-analysis of childhood leukaemia


Within the framework of the BBEMG project, the Research Unit in Public Health, Epidemiology and Health Economics studies the impact of electromagnetic fields on health using meta-analyses. Several studies have investigated the relationship between electromagnetic fields and childhood leukemia (Kabuto et al., 2006; Linet et al., 1997; Michaelis et al., 1997). Nevertheless, there are important discrepancies in this research field. Some studies found that childhood leukemia could be associated with extremely low frequency electromagnetic fields (ELF-EMF) but others studies found no relation between these variables. Therefore, it is important to conduct meta-analyses to determine whether exposure to electromagnetic fields can really increase the risk of childhood leukemia.

A meta-analysis is a statistical analysis that combines the results of several studies. This analysis provides a synthesis of the different results obtained about a specific question. Meta-analyses are considered to be the most reliable form of evidence and scientific proof (Borenstein et al. 2009). Unfortunately, procedures and statistics used in meta-analyses are often inaccurate and biased, which invalidates their conclusions (Ioannidis et al. 2015; Ioannidis 2016). Therefore, it is essential to conduct meta-analyses using the right step-by-step procedures and based on systematic reviews of the literature that take into account the PRISMA STATEMENT and PRISMA checklist (Beaudart et al., 2016; Rabenda et al., 2017; see PRISMA website in the References). In our unit, we are conducting a systematic review and a meta-analysis to clarify the relationship between ELF-EMF and childhood leukemia.

The publication describing the results of this meta-analysis can be found here.


Beaudart, Charlotte ; Rabenda, Véronique ; Bruyère, Olivier (2016) Il n’est jamais trop tard pour apprendre à (bien) lire … La revue systématique. Medi-Sphere 525: 35-38.

Borenstein M, Hedges LV, Higgins JPT, Rothstein HR (2009) Introduction to meta-analysis. New York: Wiley & Sons.

Kabuto M, Nitta H, Yamamoto S, Yamaguchi N, Akiba S, Honda Y, Hagihara J, Isaka K, Saito T, Ojima T, Nakamura Y, Mizoue T, Ito S, Eboshida A, Yamazaki S, Sokejima S, Kurokawa Y, Kubo O (2006) Childhood leukemia and magnetic fields in Japan: a case-control study of childhood leukemia and residential power-frequency magnetic fields in Japan. Int J Cancer 119: 643-50.

Linet MS, Hatch EE, Kleinerman RA, Robison LL, Kaune WT, Friedman DR, Severson RK, Haines CM, Hartsock CT, Niwa S, Wacholder S, Tarone RE (1997) Residential exposure to magnetic fields and acute lymphoblastic leukemia in children. N Engl J Med 337: 1-7.

Ioannidis JP (2016) The mass production of redundant, misleading and conflicting systematic reviews and meta-analyses. Milbank Quart 94: 485-514.

Ioannidis JP, Fanelli D, Dunne DD, Goodman SN (2015) Meta-research: evaluation and improvement of research methods and practices. PLOS BIOL 13: e1002264.

Michaelis J, Schüz J, Meinert R, Menger M, Grigat JP, Kaatsch P, Kaletsch U, Miesner A, Stamm A, Brinkmann K, Kärner H (1997) Childhood leukemia and electromagnetic fields: results of a population-based case-control study in Germany. Cancer Causes Control 8: 167-74.

PRISMA website:

Rabenda V, Beaudart C, Bruyère, O (2017) Il n’est jamais trop tard pour apprendre à (bien) lire … La Méta-Analyse. Ortho-Rhumato 15: 27-32.