Table 2

Summary of lung cancer risk estimates by treatment group

Analysis periodNumber of cases selenium/placeboRR (95% CI)PHRa (95% CI)P
1983–1993b17310.54 (0.30, 0.98)0.040.56 (0.31, 0.76)0.05
1983–199625350.70 (0.40, 1.21)0.180.74 (0.44, 1.24)0.26
  • a Cox proportional hazards model; adjusted for age, smoking status (current, former, never).

  • b Clark et al.(3) .