EGFR and lung adenocarcinoma: The results indicated that female (adjusted odds ratio [OR] 1.834, 95% confidence interval [CI] 1.069–3.144, P = 0.028), non‐smoking (adjusted OR 2.504, 95% CI 1.456–4.306, P = 0.001), lung adenocarcinoma (adjusted OR 4.512, 95% CI 2.465–8.260, P < 0.001), stage III–IV (adjusted OR 2.232, 95% CI 1.066–4.676, P = 0.033), and no symptoms of emphysema (adjusted OR 2.139, 95% CI 1.221–3.747, P = 0.008) were independent variables associated with EGFR mutations (Table 5).