Figure 1.

Effect of CHRNA5 rs16969968 on delayed smoking cessation among subjects without smoking-related disorders. Smoking-related disorders were lung cancer, chronic obstructive pulmonary disorder, and coronary heart disease. All models adjusted for age, sex, and rs16969968. Random effect models are shown, P _{heterogeneity} = .32 for group A, .027 for group B, and .0058 when all groups combined. * Individual-level data for these marked studies were available and used for the pooled analysis (n = 13 285). All statistical tests were two-sided. CHD = coronary heart disease; COPD = chronic obstructive pulmonary disorder.