Descriptive characteristics at baseline of the Lost in Italy sample by smoking habit, N (%)
| Variable | Overall sample N=6003 | Current smokers N=1400 | Former smokers N=549 | Never smokers N=4053 | P value* |
| Baseline characteristics | |||||
| Gender | |||||
| Male | 2962 (49.3) | 724 (51.7) | 322 (58.7) | 1916 (47.3) | 0.116 |
| Female | 3041 (50.7) | 677 (48.3) | 227 (41.4) | 2137 (52.7) | |
| Age | |||||
| 18–34 | 1557 (25.9) | 331 (23.6) | 86 (15.7) | 1140 (28.1) | 0.216 |
| 35–54 | 2457 (40.9) | 588 (42.0) | 165 (30.0) | 1705 (42.1) | |
| 55–74 | 1989 (33.1) | 482 (34.4) | 299 (54.4) | 1209 (29.8) | |
| Education | |||||
| Low | 911 (15.2) | 260 (18.6) | 131 (23.8) | 520 (12.8) | 0.006 |
| Intermediate | 3032 (50.5) | 691 (49.3) | 271 (49.3) | 2071 (51.1) | |
| High | 2060 (34.3) | 450 (32.1) | 148 (26.9) | 1462 (36.1) | |
| Living with children aged 0–14 | |||||
| Yes | 1707 (28.4) | 464 (33.1) | 129 (23.6) | 1114 (27.5) | <0.001 |
| No | 4296 (71.6) | 937 (66.9) | 420 (76.5) | 2939 (72.5) | |
| Geographic area | |||||
| North | 2764 (46.0) | 647 (46.2) | 254 (46.2) | 1864 (46.0) | 0.884 |
| Centre | 1201 (20.0) | 287 (20.5) | 120 (21.9) | 795 (19.6) | |
| South and Islands | 2037 (33.9) | 467 (33.4) | 176 (32.0) | 1395 (34.4) | |
| Psychological variables | |||||
| Quality of life | |||||
| Low (<6) | 789 (13.1) | 217 (15.5) | 81 (14.8) | 490 (12.1) | 0.023 |
| Intermediate (6–8) | 4534 (75.5) | 1047 (74.8) | 404 (73.6) | 3082 (76.0) | |
| High (>8) | 681 (11.3) | 136 (9.7) | 64 (11.7) | 481 (11.9) | |
| Amount of sleep | |||||
| <8 hours per night | 3982 (66.3) | 928 (66.3) | 415 (75.5) | 2639 (65.1) | 0.959 |
| ≥8 hours per night | 2021 (33.7) | 473 (33.8) | 135 (24.6) | 1414 (34.9) | |
| Anxiety | |||||
| Low | 4915 (81.9) | 1124 (80.3) | 448 (81.6) | 3343 (82.5) | 0.165 |
| High | 1088 (18.1) | 277 (19.8) | 102 (18.5) | 710 (17.5) | |
| Depression | |||||
| Low | 5143 (85.7) | 1170 (83.6) | 468 (85.3) | 3504 (86.5) | 0.051 |
| High | 861 (14.3) | 230 (16.4) | 81 (14.8) | 549 (13.6) | |
| Motor impulsivity | |||||
| Low | 2248 (37.4) | 473 (33.8) | 146 (26.6) | 1628 (40.2) | <0.001 |
| Intermediate | 1811 (30.2) | 397 (28.4) | 180 (32.8) | 1233 (30.4) | |
| High | 1945 (32.4) | 530 (37.8) | 223 (40.7) | 1192 (29.4) | |
*P value for current versus non-smokers (ie, former and never smokers).