| Metropolitan | Nonmetropolitan | Model 1: Not adjusted for smoking | Model 2: Adjusted for smoking | ||||
---|---|---|---|---|---|---|---|---|
 | Rate | Count | Person-years | Rate | Count | Person-years | P-value | P-value |
Overall incidence | 29.7 | 8302 | 40,106,205 | 34.8 | 1630 | 5,297,867 | <.0001* | 0.19 |
Stage | ||||||||
 Localized | 5.2 | 1462 | 40,106,205 | 6.0 | 285 | 5,297,867 | 0.02* | 0.83 |
 Regional | 6.3 | 1792 | 40,106,205 | 7.2 | 336 | 5,297,867 | 0.04* | 0.15 |
 Distant | 15.4 | 4317 | 40,106,205 | 16.7 | 784 | 5,297,867 | 0.02* | 0.02* |
 Unstaged | 2.7 | 731 | 40,106,205 | 4.9 | 225 | 5,297,867 | < 0.0001* | < 0.0001* |
Sex | ||||||||
 Male | 39.5 | 4963 | 20,073,510 | 45.7 | 1004 | 2,662,232 | < 0.0001* | 0.24 |
 Female | 21.9 | 3339 | 20,032,695 | 25.4 | 626 | 2,635,635 | 0.0003* | 0.46 |