Association of baseline factors with 4-week self-reported quitting among eligible smokers (Group A+B+C)
| Quit by 4 weeks (n=323) | Not quitting by 4 weeks (n=1827) | Univariate OR (95% CI) | p-value# | |
| Age group (years) | 0.55 | |||
| <60 | 77 (23.8) | 411 (22.5) | 1.00 | (0.41) |
| 60–64 | 90 (27.9) | 452 (24.7) | 1.06 (0.76–1.48) | |
| 65–69 | 64 (19.8) | 426 (23.3) | 0.80 (0.56–1.15) | |
| 70–74 | 52 (16.1) | 317 (17.4) | 0.88 (0.60–1.28) | |
| ≥75 | 40 (12.4) | 221 (12.1) | 0.97 (0.64–1.46) | |
| Sex | 0.03 | |||
| Female | 142 (44.0) | 924 (50.6) | 1.00 | |
| Male | 181 (56.0) | 903 (49.4) | 1.30 (1.02–1.65) | |
| IMD quintile | 0.18 | |||
| 1 (most deprived) | 127 (39.3) | 777 (42.5) | 0.78 (0.51–1.19) | (0.07) |
| 2 | 48 (14.9) | 339 (18.6) | 0.68 (0.42–1.09) | |
| 3 | 61 (18.9) | 279 (15.3) | 1.05 (0.66–1.67) | |
| 4 | 54 (16.7) | 274 (15.0) | 0.94 (0.59–1.51) | |
| 5 (least deprived) | 33 (10.2) | 158 (8.6) | 1.00 | |
| Ethnicity, self-reported¶ | 0.32 | |||
| White | 312 (96.6) | 1736 (95.0) | 1.00 | |
| Black | 2 (0.6) | 27 (1.5) | 0.41 (0.10–1.74) | |
| Asian | 6 (1.9) | 29 (1.6) | 1.15 (0.47–2.80) | |
| Other | 2 (0.6) | 25 (1.4) | 0.45 (0.10–1.89) | |
| Prefer not to say+ | 1 (0.3) | 5 (0.3) | ||
| Missing | 0 (0.0) | 5 (0.3) | ||
| Education | 0.05 | |||
| No qualifications | 169 (52.3) | 1090 (59.7) | 1.00 | (0.02) |
| O-levels or equivalent | 78 (24.1) | 381 (20.9) | 1.32 (0.99,1.77) | |
| A-levels and above | 73 (22.6) | 342 (18.7) | 1.38 (1.02–1.86) | |
| Prefer not to say+ | 3 (0.9) | 9 (0.5) | ||
| Missing | 0 (0.0) | 5 (0.3) | ||
| Cigarettes per day | 0.002 | |||
| ≤10 | 140 (43.3) | 566 (31.0) | 1.00 | (0.001) |
| 11–20 | 127 (39.3) | 883 (48.3) | 0.58 (0.45–0.76) | |
| 21–30 | 32 (9.9) | 198 (10.8) | 0.65 (0.43–0.99) | |
| >30 | 8 (2.5) | 57 (3.1) | 0.57 (0.26–1.22) | |
| Refused | 14 (4.3) | 90 (4.9) | 0.63 (0.35–1.14) | |
| Missing | 2 (0.6) | 33 (1.8) | ||
| COPD primary care code | 0.10 | |||
| Yes | 71 (22.0) | 479 (26.2) | 0.79 (0.60–1.05) | |
| No | 252 (78.0) | 1348 (73.8) | 1.00 | |
| Respiratory symptoms§ | 0.77 | |||
| Yes | 257 (79.6) | 385 (21.1) | 1.04 (0.78–1.40) | |
| No | 66 (20.4) | 1435 (78.5) | 1.00 | |
| Missing | 0 (0.0) | 7 (0.4) | ||
| MRC dyspnoea score | 0.27 | |||
| 0–1 | 262 (81.1) | 1427 (78.1) | 1.00 | |
| 2–4 | 61 (18.9) | 393 (21.5) | 0.85 (0.63–1.14) | |
| Missing | 0 (0.0) | 7 (0.4) | ||
| WHO performance status | ||||
| 0–1 | 293 (90.7) | 1617 (88.5) | 1.00 | 0.31 |
| 2–4 | 30 (9.3) | 203 (11.1) | 0.82 (0.55–1.22) | |
| Missing | 0 (0.0) | 7 (0.4) | ||
| Perceived personal risk of cancer versus other smokers | 0.25 | |||
| Lower | 44 (13.6) | 198 (10.8) | 1.00 | (0.60) |
| About the same | 206 (63.8) | 1191 (65.2) | 0.78 (0.54–1.11) | |
| Higher | 64 (19.8) | 339 (18.6) | 0.85 (0.56–1.30) | |
| Refused | 7 (2.2) | 67 (3.7) | 0.47 (0.20–1.09) | |
| Missing | 2 (0.6) | 32 (1.8) | ||
| Fagerström nicotine dependency | 0.04 | |||
| <4 (less dependent) | 136 (42.1) | 624 (34.2) | 1.00 | (0.02) |
| 4–6 (moderately dependent) | 123 (38.1) | 782 (42.8) | 0.72 (0.55–0.94) | |
| 7–10 (highly dependent) | 35 (10.8) | 223 (12.2) | 0.72 (0.48–1.08) | |
| Missing | 29 (9.0) | 198 (10.8) | ||
| Motivation to stop smoking | <0.001 | |||
| Don't want to/think I should but don't want to | 60 (18.6) | 820 (44.9) | 1.00 | (<0.001) |
| Want to but haven't thought/ don't know when | 76 (23.5) | 350 (19.2) | 2.97 (2.07–4.26) | |
| Want to and hope to soon | 102 (31.6) | 409 (22.4) | 3.41 (2.43–4.79) | |
| Really want to and intend to in next 1/3 months | 71 (22.0) | 180 (9.9) | 5.39 (3.69–7.88) | |
| Already quit | 9 (2.8) | 15 (0.8) | 8.20 (3.45–19.51) | |
| Refused | 3 (0.9) | 20 (1.1) | ||
| Missing | 2 (0.6) | 33 (1.8) | ||
| Serious quit attempts in the past year | <0.001 | |||
| 0 | 187 (57.9) | 1401 (76.7) | 1.00 | (<0.001) |
| 1 | 80 (24.8) | 215 (11.8) | 2.79 (2.07–3.76) | |
| ≥2 | 54 (16.7) | 170 (9.3) | 2.38 (1.69–3.35) | |
| Refused | 0 (0.0) | 7 (0.4) | ||
| Missing | 2 (0.6) | 34 (1.9) | ||
| Self-efficacy of quitting | <0.001 | |||
| Not at all | 38 (11.8) | 386 (21.1) | 1.00 | (<0.001) |
| Slightly/somewhat | 91 (28.2) | 572 (31.3) | 1.62 (1.08–2.41) | |
| Moderately/extremely | 189 (58.5) | 790 (43.2) | 2.43 (1.68–3.52) | |
| Refused | 3 (0.9) | 46 (2.5) | 0.66 (0.20–2.23) | |
| Missing | 2 (0.6) | 33 (1.8) |
Data are presented as n (%), unless otherwise stated. IMD: Index of Multiple Deprivation; MRC: Medical Research Council; WHO: World Health Organization. #: global p-value for non-ordered factors only and global p-value with (p-value for trend) for ordered factors (excluding “refused”); ¶: self-reported at eligibility check on mobile van; +: excluded from regression due to small numbers; §: breathlessness, chronic cough, sputum, winter bronchitis, wheeze.