Table 1

Assessing the multiplicative relationship of smoking and asbestos in lung cancer risk

Estimate*Study typeV (95% CI)Heterogeneity χ2Degrees of freedom
*References and fuller details given elsewhere4 except where stated.
C, case–control; P, prospective.
V is the ratio of the asbestos relative risk in smokers to that in non-smokers.
1.DeKlerkCC1.25 (0.19 to 8.08)
2.MartischnigCC2.89 (0.87 to 9.62)
3.Pastorino, no PAHCC0.64 (0.10 to 4.06)
4.Pastorino, PAHCC1.01 (0.13 to 7.94)
5.BovenziCC0.86 (0.31 to 2.39)
6.KjuusCC1.52 (0.39 to 5.93)
7.Blot, GeorgiaCC1.26 (0.54 to 2.93)
8.Blot, VirginiaCC0.84 (0.39 to 1.81)
9.Blot, FloridaCC0.72 (0.22 to 2.36)
10.McDonaldP0.61 (0.25 to 1.49)
11.ZhuP1.60 (0.43 to 5.90)
12.MeurmanP1.19 (0.07 to 20.4)
13.Berry, 1960–70 M+FP0.61 (0.10 to 25.7)
14.Selikoff and HammondP1.22 (0.32 to 10.4)
15.SelikoffP0.19 (0.07 to 0.61)
16.HammondP0.95 (0.47 to 2.21)
17.Berry, 1971–80 M+FP0.33 (0.13 to 1.25)
18.Liddell3P0.56 (0.20 to 1.56)
19.Berry, 1960–70 FP1.47 (0.22 to 50.0)
Original analysis
Estimates1–16All0.90 (0.67 to 1.20)14.8815
Revised analysis
Estimates1–12, 14–19All0.83 (0.63 to 1.08)18.3917
Estimates1–9CC1.08 (0.74 to 1.59) 4.33 8
Estimates10–12, 14–19P0.63 (0.43 to 0.92)10.17 8
Revised analysis with exclusions
Estimates1–3, 5–10, 15–19All0.79 (0.59 to 1.05)17.0013
Estimates1–3, 5–9CC1.09 (0.74 to 1.60) 4.33 7
Estimates10, 15–19P0.54 (0.35 to 0.82) 6.95 5