Table 1.
Cases (n = 1,004) |
Controls (n = 848) |
P Valuea | |||||
No. | % | Median (SD) | No. | % | Median (SD) | ||
Age, years | 66.2 (10.8) | 58.4 (11.4) | <0.001 | ||||
Caucasian race | 973 | 97 | 824 | 97 | 0.75 | ||
Education | |||||||
Less than high school | 130 | 15 | 73 | 9 | <0.001 | ||
High school | 348 | 40 | 278 | 33 | 0.003 | ||
Some college or college degree | 385 | 45 | 485 | 58 | <0.001 | ||
Missing data | 141 | 12 | |||||
Smoking status | |||||||
Never smoker | 102 | 10 | 332 | 39 | <0.001 | ||
Current smoker | 430 | 43 | 188 | 22 | <0.001 | ||
Former smoker | 472 | 47 | 328 | 39 | <0.001 | ||
Pack-years of smoking | |||||||
Former smoker | 41.7 (30.5) | 16.6 (20.7) | <0.001 | ||||
Current smoker | 48.4 (32.5) | 31.9 (25.3) | <0.001 | ||||
Histologic type | |||||||
Adenocarcinoma | 455 | 45 | |||||
Squamous-cell carcinoma | 150 | 15 | |||||
Bronchoalveolar carcinoma | 121 | 12 | |||||
Other | 278 | 28 | |||||
Nulliparity | 149 | 15 | 117 | 14 | 0.52 |
Abbreviation: SD, standard deviation.
P value from a χ2 test for categorical variables and a t test for continuous variables. All P values are 2-sided.