Table 1

Cohort characteristics and comparison between responders and non-responders at 3 months postnatal

CharacteristicAll cohort
N (%)
Responders at 3 months postnatal
N (%)
Non-responders and withdrawals at 3 months postnatal
N (%)
p Value
N=850N=476N=374
Smoking behaviour baseline
 Recent ex-smoker362 (43.4)235 (50.1)127 (34.7)
 ≤5 cigarettes per day191 (22.9)105 (22.4)86 (23.5)
 6–10 cigarettes per day151 (18.08)71 (15.1)80 (21.9)
 ≥11 cigarettes per day131 (15.4)58 (12.4)73 (20.0)<0.0001
Age (years) Mean (SD)25.8 (5.5)26.5 (5.6)24.8 (5.3)<0.0001
Ethnicity
 White British751 (89.0)421 (89.0)330 (89.0)
 Other ethnicity93 (11.0)52 (11.0)41 (11.1)0.0007
Highest qualification
 No qualifications155 (18.2)62 (13.0)94 (25.1)
 GCSEs or equivalent355 (41.8)184 (38.7)171 (45.7)
 AS/A-Levels or equivalent174 (20.5)118 (24.8)56 (15.0)
 Degree or equivalent133 (15.7)95 (20.0)38 (10.2)
 Other qualification33 (2.9)17 (3.6)16 (4.3)<0.0001
Age left education
 ≤16 years of age469 (56.4)232 (50.0)237 (64.6)
 ≥17 years of age334 (40.2)211 (45.4)123 (33.5)
 Still in full-time education28 (2.4)21 (4.5)7 (1.9)<0.0001
Employment
 Paid work, manual158 (18.7)102 (21.5)56 (15.0)
 Paid work, non-manual180 (21.3)131 (27.6)49 (13.1)
 Paid work, unclear whether manual/non-manual45 (5.3)27 (5.7)18 (4.8)
 Unemployed201 (23.7)92 (19.4)109 (29.2)
 Full-time parent219 (25.9)97 (20.5)122 (32.7)
 Full-time student23 (2.7)13 (2.7)10 (2.7)
 Other21 (2.5)12 (2.5)9 (2.4)<0.0001
Indices Multiple Deprivation score (IMD)*
 1st tertile284 (33.6)178 (37.4)106 (28.8)
 2nd tertile279 (33.1)162 (34.0)117 (31.8)
 3rd tertile281 (33.3)136 (28.6)145 (39.4)0.002
Baseline heaviness of smoking index (smokers only)
 Low addiction321 (67.6)171 (72.8)150 (62.5)
 Moderate addiction146 (30.7)61 (26.0)85 (35.4)
 High addiction8 (1.7)3 (1.3)5 (2.1)0.06
Partner smoking baseline
 Partner does not smoke tobacco499 (59.1)172 (36.4)122 (32.9)
 Partner smokes tobacco294 (34.8)279 (58.9)220 (59.3)
 No partner51 (6.0)22 (4.7)29 (7.8)0.12
  • *Higher score reflects greater deprivation.

  • GCSE, General Certificate of Secondary Education.