an increasing trendp = 0.06
The individual RRs for natural background level of expo- sure exhibited an increasing trend (RRs = 1.00, 1.03, and 1.55; p = 0.06).
The individual RRs for natural background level of expo- sure exhibited an increasing trend (RRs = 1.00, 1.03, and 1.55; p = 0.06).
Background 'y-radiation also showed a slight trend in risk for lung cancer, with an odds ratio of 1.1 (CI, 0.9-1.4) (11).
Hence, this relationship is probably due to other con- founders or risk factors not accounted for in this analysis. We observed a borderline significant increasing trend in risk with increasing natur- al background radiation for lung cancer in males, which is similar to the findings of Hatch et al.