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Use of mobile phones and risk of brain tumours: update of Danish cohort study

BMJ 2011; 343 doi: (Published 20 October 2011) Cite this as: BMJ 2011;343:d6387

The Danish Cellphone Subscriber Study on the Risk of Cancer Among Subscribers Is Fundamentally Flawed

Either being a male cellphone subscribers were significantly
protected from all cancers or this study has such fundamental flaws that
it becomes nonsensical.
Immediately in Table 1, the very first result found a statistically
significant protection from all cancers, OR=0.96, 95% CI=0.95-0.85. The
calculated p-value for this finding is 1.5*10-7, equivalent to one chance
in 6.6 million that was a random result.

When the authors state, "there was no increased risks of tumours of
the central nervous system," it was technically correct but only by
removing important from the statement. Placed in context this statement
might have been, "While there was no increased risk of tumours of the
central nervous system, there was significant protection from all cancers
in men.

Other Rapid Responses have addressed why any risk of central nervous
tumours would be highly unlike to be found because of other fundamental

Competing interests: No competing interests

02 November 2011
L Lloyd Morgan
Sr. Research Fellow
Environmental Health Trust