Table 1. Meta-analyses of the risk of breast or prostate cancer in flight personnel (4).

	Number of studies	RR (95% CI), fixed effects	RR (95% CI), random effects
Breast cancer
All studies	12	1.7 (1.4–2.1)	1.7 (1.4–2.1)
Cohort studes	9	1.6 (1.3–2.0)	1.6 (1.3–2.0)
Case-control studies	3	2.8 (1.3–6.0)	2.8 (1.3–6.2)
SIR	5	1.8 (1.4–2.3)	1.8 (1.4–2.3)
SMR	3	1.2 (0.7–1.9)	1.2 (0.7–1.9)
Europe	10	1.6 (1.2–2.1)	1.6 (1.2–2.1)
North America	2	1.8 (1.3–2.6)	1.8 (1.3–2.6)
Prostate cancer
All studies	9	1.4 (1.1–1.8)	1.4 (1.1–1.8)
SIR	6	1.5 (1.1–1.9)	1.5 (1.1–1.9)
SMR	3	1.1 (0.7–1.8)	1.1 (0.7–1.8)
Europe	8	1.1 (0.8–1.5)	1.1 (0.8–1.5)

(Reprinted with the kind permission of Springer Science + Business Media); SIR, standardized incidence rate; SMR, standardized mortality rate; RR, relative risk; CI, confidence interval