Table 2

Outcomes and effect sizes of interventions to support smoking cessation

Type of outcomeStudyMore intensive interventionLess intensive interventionComparisonEffect
Objective measures
 Biochemically verified smoking cessationArdron et al1901 (3%)
Canga et al*2025 (17%)3 (2%)Incidence ratio (95% CI)7.5 (2.3 to 24.4)
Hokanson et al*234 (7%)2 (4%)χ2 test for difference in abstinence ratep=0.077
Sawicki et al182 (5%)7 (16%)Difference in point prevalence of cessationReported as not significant
 Urinary cotinine–creatinine ratio, µg/mgArdron et al197.6 (4.5)6.7 (4.4)
 Breath CO (µL/L)Ardron et al1918.2 (10.0)19.4 (8.9)
 HbA1c <7% (53 mmol/mol)Hokanson et al2335 (61%)43 (75%)Difference in proportion of patients achieving HbA1c <7%Reported as not significant
Self-reported measures
 7-day abstinenceNg et al*2214 (37%)10 (30%)Allocation effect in logistic regression modelReported as not significant
Thankappan et al*2158 (52%)14 (13%)Adjusted OR (95% CI)8.4 (4.1 to 17.1)
 Number of cigarettes smoked dailyCanga et al2015.5†18.1†Difference in change in mean cigarettes per day from baseline (95% CI)−3.0 (−1.1 to −4.9)
 >50% reduction in number of cigarettes smoked dailyThankappan et al2120 (18%)25 (22%)Adjusted OR (95% CI)1.9 (0.8 to 4.1)
 Attempts to quit or reduce smokingNg et al2221 (55%)16 (48%)Allocation effect in logistic regression modelReported as not significant
 Incidence of smoking relapseCanga et al2049 (33%)14 (11%)Difference (95% CI) in incidence of relapse22.8% (13.6 to 32.0)
  • Data presented as number of events (%) or mean (SD).

  • *Reported as a primary outcome.

  • †SDs not reported.

  • CO, carbon monoxide; HbA1c, glycated haemoglobin.