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Papers

Childhood cancer in relation to distance from high voltage power lines in England and Wales: a case-control study

BMJ 2005; 330 doi: https://doi.org/10.1136/bmj.330.7503.1290 (Published 02 June 2005) Cite this as: BMJ 2005;330:1290

Re: Childhood cancer in relation to distance from high voltage power lines: Some important considerations

There may be potential bias in the cases for which addresses could
not be identified. Presumably, power lines are in more developed areas,
where addresses might be more durable over time. Distances could not be
calculated for some 12% of cases. A modest bias favoring inclusion of
cases close to power lines and exclusion of cases far from power lines
(because the address couldn't be identified) might produce the observed
result.

Presumably a stability of address effect due to proximity to power
lines would extend beyond 600 meters. Examination of the data set for
excess cases at large but fixed distances, for example 1,000 to 1,500
meters might show such an effect.

Competing interests:
None declared

Competing interests: No competing interests

03 June 2005
David R. Whitlock
engineer
Separation Technologies