Table 2.

Sex-specific pooled relative risks (RR) and ratio of relative risks (RRR) for lung cancer associated with smoking

	RR in women	RR in men	RRR
Age adjusted
Former versus never	2.82 (2.25 to 3.54)	3.01 (2.23 to 4.08)	0.88 (0.69 to 1.14)
Current versus not	7.48 (5.29 to 10.60)	8.78 (6.13 to 12.57)	0.81 (0.62 to 1.04)
Multiple adjusted
Former versus never	3.14 (2.45 to 4.03)	3.13 (2.06 to 4.76)	0.89 (0.69 to 1.13)
Current versus not	6.99 (5.09 to 9.59)	7.33 (4.90 to 10.96)	0.92 (0.72 to 1.16)
Maximum adjusted
Former versus never	2.92 (2.35 to 3.63)	3.08 (2.31 to 4.11)	0.86 (0.71 to 1.05)
Current versus not	7.32 (5.58 to 9.61)	8.05 (5.90 to 10.98)	0.89 (0.73 to 1.08)
Cigarettes per day among current smokers versus never (maximum available adjusted)
10 or less	5.30 (3.52 to 7.97)	4.97 (2.74 to 9.03)	0.99 (0.65 to 1.52)
10 to 19	10.67 (7.43 to 15.33)	8.93 (4.90 to 16.28)	1.11 (0.75 to 1.64)
20 or more	17.09 (12.11 to 24.11)	14.61 (8.33 to 25.59)	0.94 (0.69 to 1.30)

Multiple adjusted includes anything that adjusted for more than just age. Maximum available adjustment refers to the most adjustments provided in the study. For some studies, this would have been age adjusted whereas other studies adjusted for more factors than age only (ie, multiple adjusted). These covariates are listed in table 1.