| Study | Number of cases | Number of controls | Source of controls | Relative risk (95% confidence interval) | ||
|---|---|---|---|---|---|---|
| Ever smoked | Current smokers | Former smokers | ||||
| Byers et al. 1983 | 274 | 1,034 | Hospital | 0.9 * | ||
| Smith et al. 1984 | 58 | 612 | Population | 0.8 (0.4-1.6) ** | ||
| Tzonou et al. 1984 | 150 | 250 | Hospital | 0.8§ | ||
| Franks et al. 1987b | 494 | 4,238 | Population | 1.0 (0.9-1.3) | 1.1 (0.9-1.4) | 0.9 (0.7-1.2) |
| Stockwell and Lyman 1987 | 889 | 3,921 | Other cancers | 1.1 (0.6-1.9) >§<§ | 0.9 (0.7-1.2) | |
| Hartge et al. 1989 | 296 | 343 | Hospital | 0.8 (0.6-1.3) | 1.3 (0.9-2.0) | |
| Kato et al. 1989 | 417 | 8,920 | Other cancers | 0.8 (0.6-1.1) | ||
| Shu et al. 1989 | 229 | 229 | Hospital | 1.8 (0.7-4.8) | ||
| Polychronopoulou et al. 1993 | 189 | 200 | Hospital visitor | 1.0 (0.5-1.8) | ||
Authors stated that relative risk was not statistically significant.
Continuous smokers.
p = 0.08.
Current smokers of >40 cigarettes/day.
From: Chapter 3. Health Consequences of Tobacco Use Among Women
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