Table 1. General characteristics of participants compared before and after public advertisementa.
| Characteristics | Before (n=1,887) | After (n=3,805) | Total (n=5,692) | P valueb |
|---|---|---|---|---|
| Age | ||||
| 55–59 years | 606 (32.1) | 1,179 (31.0) | 1,785 (31.4) | 0.03 |
| 60–64 years | 640 (33.9) | 1,269 (33.4) | 1,909 (33.5) | |
| 65–69 years | 361 (19.1) | 853 (22.4) | 1,214 (21.3) | |
| 70–74 years | 280 (14.8) | 504 (13.3) | 784 (13.8) | |
| Sex | ||||
| Male | 1,846 (97.8) | 3,724 (97.9) | 5,570 (97.9) | 0.91 |
| Female | 41 (2.2) | 81 (2.1) | 122 (2.1) | |
| Smoking status | ||||
| Current smoker | 982 (52.0) | 2,070 (54.4) | 3,052 (53.6) | 0.09 |
| Former smoker | 905 (48.0) | 1,735 (45.6) | 2,640 (46.4) | |
| Quit smoking for <5 years | 374 (41.3) | 685 (39.5) | 1,059 (40.1) | 0.49 |
| Quit smoking for 5–9 years | 226 (25.0) | 426 (24.6) | 652 (24.7) | |
| Quit smoking for 10–15 years | 305 (33.7) | 624 (36.0) | 929 (35.2) | |
| Pack-years (PY) of smoking history | ||||
| 30–34 PY | 722 (38.3) | 1,169 (30.7) | 1,891 (33.2) | <0.01 |
| 35–39 PY | 281 (14.9) | 628 (16.5) | 909 (16.0) | |
| 40–44 PY | 418 (22.2) | 862 (22.7) | 1,280 (22.5) | |
| ≥45 PY | 466 (24.7) | 1,146 (30.1) | 1,612 (28.3) | |
| Education levelc | ||||
| Under middle school | 496 (26.3) | 834 (21.9) | 1,330 (23.4) | <0.01 |
| High school | 764 (40.5) | 1,488 (39.1) | 2,252 (39.6) | |
| Undergraduate or higher | 623 (33.0) | 1,479 (38.9) | 2,102 (36.9) | |
| Household income (million KRW/month)c,d | ||||
| <2.0 | 719 (38.1) | 1,471 (38.7) | 2,190 (38.5) | 0.24 |
| 2.0–3.9 | 714 (37.8) | 1,496 (39.3) | 2,210 (38.8) | |
| ≥4.0 | 447 (23.7) | 829 (21.8) | 1,276 (22.4) | |
| Drinking alcohol (days per week)c | ||||
| None | 590 (31.3) | 1,138 (29.9) | 1,728 (30.4) | 0.17 |
| 1–4 | 985 (52.2) | 2,077 (54.6) | 3,062 (53.8) | |
| ≥5 | 228 (12.1) | 417 (11.0) | 645 (11.3) | |
| Moderate intensity aerobic exercise (days per week) c | ||||
| None | 790 (41.9) | 1,522 (40.0) | 2,312 (40.6) | 0.35 |
| 1–4 | 612 (32.4) | 1,295 (34.0) | 1,907 (33.5) | |
| ≥5 | 220 (11.7) | 433 (11.4) | 653 (11.5) | |
| Family history of lung cancer | 575 (10.1) | |||
| No | 1,725 (91.4) | 3,392 (89.2) | 5,107 (89.9) | <0.01 |
| Yes | 162 (8.6) | 413 (10.9) | 575 (10.1) | |
| Medical history of lung diseasee,f | ||||
| None | 1,655 (87.7) | 3,317 (87.2) | 4,969 (87.3) | 0.57 |
| Tuberculosis | 1,34 (7.1) | 276 (7.3) | 410 (7.2) | |
| COPD | 59 (3.1) | 144 (3.8) | 203 (3.6) | |
| Pneumonia | 37 (2.0) | 76 (2.0) | 113 (2.0) | |
| ETCg | 17 (1.0) | 24 (0.6) | 41 (0.7) |
K-LUCAS, Korean Lung Cancer Screening Project; KRW, Korean won; COPD, chronic obstructive pulmonary disease; ARDS, acute respiratory distress syndrome. a, advertisement (newspaper) to general population was published on the September 22, 2017, but it generally takes 1 week for the participants to receive the screening. Here, we compared the participants’ characteristics before and after October 1, 2017, as we assumed that the advertisement effect began to occur around this date; b, the association between public advertisements and participant characteristics was evaluated using the chi-square test; c, data missing because the participants did not answer the survey; d, 1 million KRW is approximately 900 USD; e, one participant can develop more than one type of lung disease; f, Chi-square test was used to examine the association between public advertisement (before and after advertisement) and participant with any known medical history of lung diseases; g, includes solitary nodule, emphysema, fibrothorax, interstitial lung disease, and thickening of pleura.