Table 2

Relative risk of lung cancer by radon concentration (Bq/m3) in homes 5-34 years previously

Mean (Bq/m3)
Range of measured valuesMeasured valuesEstimated usual valuesNo of lung cancer cases/controlsRelative risk (95% floated CI)
<251721566/14741.00 (0.87 to 1.15)
25-4939421999/39051.06 (0.98 to 1.15)
50-9971692618/50331.03 (0.96 to 1.10)
100-1991361191296/22471.20 (1.08 to 1.32)
200-399273236434/9361.18 (0.99 to 1.42)
400-799542433169/4981.43 (1.06 to 1.92)
≥800120467866/1152.02 (1.24 to 3.31)
Total104/97*90/86*7148/14 208
  • * Cases/controls. Weighted average for controls, with weights proportional to study specific numbers of cases. Note that as random variation in measured values is approximately logarithmic (so measurement twice as big as usual value is about as likely as measurement half as big as usual value), means of measured values slightly exceed means of estimated usual values.