October 20, 2011

expert reaction to use of mobile phones and risk of brain tumours, as published in the BMJ

New research added further evidence in the debate over the potential link between mobile phone use and cancer risk. The SMC also sent out a before the headlines analysis.

Prof David Spiegelhalter, Winton Professor of the Public Understanding of Risk at the University of Cambridge, said:

“The mobile phone records only go up to 1995 and so the comparison is mainly between early and late adopters, but the lack of any effect on brain tumours is still very important evidence.

“This is a very powerful and important study, but it is only made possible by all Danes having a personal ID number that allows their early mobile phone usage to be related to their health, all without any personal contact. In the UK this would be impossible, and the whole idea very controversial.”

Prof Malcolm Sperrin, Director of Medical Physics at Royal Berkshire Hospital, and Fellow of the Institute of Physics and Engineering in Medicine, said:

“This study is very large in terms of the number of people involved, is large in terms of the number of usage of the phones and also has a random nature being based on the purchase of a telephone contract rather than being a sub-group. The findings clearly reveal that there is no additional overall risk of developing a cancer in the brain although there does seem to be some minor, and not statistically significant, variations in the type of cancer.

“The study is extremely well conducted with confounding factors such as smoking being considered. The statistical analysis is rigorous and limitations such as individual hours used rather than length of contract being held have been identified and addressed. There may be some benefit is further breaking the data down into age groups but the authors find no correlation of risk to phone use so such a further division of the data may be pointless.

“This paper supports most other reports which do not find any detrimental effects of phone use under normal exposures.”

‘Use of mobile phones and risk of brain tumours: update of Danish cohort study’, Patrizia Frei et al, published in the BMJ on Thursday 20 October 2011. Before The Headlines analysis: Use of Mobile Phones and Risk of Brain Tumours: update of a Danish Cohort Study. Before The Headlines is a service provided to the SMC by volunteer statisticians: members of the Royal Statistical Society and Statisticians in the Pharmaceutical Industry. A list of contributors, including affiliations, is available here.