Cochrane Clinical Answers - Fulltext - Can providing incentives to stop smoking to adult smokers of mixed populations increase quit rates?

Question:Can providing incentives to stop smoking to adult smokers of mixed populations increase quit rates?

Clinical Answer:

Low-quality evidence suggests that providing incentives to adult smokers from mixed populations improves smoking cessation rates at follow-up periods of 6 months but not longer. Clinical trials have investigated various rewards for smoking cessation in locations such as medical clinics, villages, urban communities, academic institutions, and worksites among people of corresponding diversity. Typically, the intervention group received a reward such as lottery/raffle tickets/vouchers or cash for abstinence, and the control group was simply monitored. Individuals were assessed by self-report or through biochemical methods. In some trials, abstinence rates were compared between contingent reward and automatic reward groups, with the latter serving as the control group. Studies did not assess adverse events associated with incentives.

Full outcome data is detailed below:

1.Smoking cessation incentives versus control in mixed populations

  • Population, Intervention, Comparator

    Population:

    Smokers (26% to 100% men across studies; mean/median age range 37 to 52 years). Studies were set in clinics or health centers (7 trials), in villages served by community health workers (1 trial), in an academic institution (2 trials), in an urban community (1 trial), and the rest in worksites. Most trials used some form of multi-component support program: self-help (4 trials), individual or group counseling (4 trials), standard counselling with spirometry feedback and information on local smoking cessation services (1 trial), guiding participants towards smoking cessation resources (1 trial), aversive smoking (1 trial), nicotine replacement therapy (3 trials) or adding encouragement and peer pressure from deposit-collectors to support participants (2 trials). Only four trials reported that most participants were willing to quit

    Intervention:

    Incentives such as lottery or raffle tickets (3 trials), cash payments (7 trials), saving account with topped up contributions and rewards for abstinence (3 trials). Two trials compared the effects of fixed automatic payments with payments contingent upon cessation, with the guaranteed payment regimen generally serving as the control condition. Another trial allocated points for abstinence, which translated into vouchers. Intervention lasted 1 to 12 months (where reported)

    Comparator:

    Control: monitoring only or no additional intervention

  • OUTCOME 1.1: Smoking cessation in mixed populations

    Narrative result:

    Smoking cessation rates in mixed populations were higher in people who had received incentives, when considering all the studies with a follow-up of 6 to 24 months. When studies were reported by duration of follow-up, only the ones with a follow-up of 6 months showed similar results to the main analysis. Click below for full details.

    Reference:
    Cahill K, Hartmann-Boyce J, Perera R. Incentives for smoking cessation. Cochrane Database of Systematic Reviews 2015, Issue 5. Art. No.: CD004307. DOI: 10.1002/14651858.CD004307.pub5. [Review search date: December 2014]
    • Subgroup analysis 1.1.1: Smoking cessation in mixed populations - [subgroup: Longest follow-up; 6 to 24 months]
      Quality of the evidence:

      The reviewers performed a GRADE assessment of the quality of evidence for this outcome at this time point and stated that the evidence was low quality. See Summary of findings from Cochrane review

      Narrative result:

      20 RCTs with 7715 participants found that more people who received incentives stopped smoking compared with control.

      Relative effect or mean difference:

      There was a statistically significant difference between groups, in favor of incentives (odds ratio 1.42, 95% CI 1.19 to 1.69).

      Forest plot from Cochrane Review

      Absolute effect:

      112 per 1000 people (95% CI 95 to 132) with incentives compared with 84 per 1000 people with no incentives.

      Reference:
      Cahill K, Hartmann-Boyce J, Perera R. Incentives for smoking cessation. Cochrane Database of Systematic Reviews 2015, Issue 5. Art. No.: CD004307. DOI: 10.1002/14651858.CD004307.pub5. [Review search date: December 2014]
    • Subgroup analysis 1.1.2: Smoking cessation in mixed populations - [subgroup: Six months]
      Risk of bias of studies:

      The reviewers did not perform a GRADE assessment of the quality of evidence for this outcome. Of the 19 studies, 11 (58%) failed to report adequate allocation concealment, 16 (84%) did not report adequate blinding of participants/carers/outcome assessors and 8 (50%) had high or unclear numbers of withdrawals.

      Narrative result:

      19 RCTs with 6945 participants found that more people who received incentives stopped smoking compared with control.

      Relative effect or mean difference:

      There was a statistically significant difference between groups, in favor of incentives (odds ratio 1.72, 95% CI 1.43 to 2.08).

      Forest plot from Cochrane Review

      Reference:
      Cahill K, Hartmann-Boyce J, Perera R. Incentives for smoking cessation. Cochrane Database of Systematic Reviews 2015, Issue 5. Art. No.: CD004307. DOI: 10.1002/14651858.CD004307.pub5. [Review search date: December 2014]
    • Subgroup analysis 1.1.3: Smoking cessation in mixed populations - [subgroup: 12 months]
      Risk of bias of studies:

      The reviewers did not perform a GRADE assessment of the quality of evidence for this outcome. Of the 8 studies, 6 (75%) failed to report adequate allocation concealment, 7 (88%) did not report adequate blinding of participants/carers/outcome assessors and 3 (38%) had unclear numbers of withdrawals.

      Narrative result:

      Eight RCTs with 4245 participants found no statistically significant difference between groups.

      Relative effect or mean difference:

      There was a statistically significant difference between groups, in favor of incentives (odds ratio 1.17, 95% CI 0.94 to 1.46).

      Forest plot from Cochrane Review

      Reference:
      Cahill K, Hartmann-Boyce J, Perera R. Incentives for smoking cessation. Cochrane Database of Systematic Reviews 2015, Issue 5. Art. No.: CD004307. DOI: 10.1002/14651858.CD004307.pub5. [Review search date: December 2014]
    • Subgroup analysis 1.1.4: Smoking cessation in mixed populations - [subgroup: 18 months]
      Risk of bias of studies:

      The reviewers did not perform a GRADE assessment of the quality of evidence for this outcome. The study failed to report adequate allocation concealment and random sequence generation, reported adequate blinding of outcome assessors but had unclear numbers of withdrawals.

      Narrative result:

      One RCT with 561 participants found no statistically significant difference between groups.

      Relative effect or mean difference:

      There was a statistically significant difference between groups, in favor of incentives (odds ratio 1.59, 95% CI 0.89 to 2.83).

      Forest plot from Cochrane Review

      Reference:
      Cahill K, Hartmann-Boyce J, Perera R. Incentives for smoking cessation. Cochrane Database of Systematic Reviews 2015, Issue 5. Art. No.: CD004307. DOI: 10.1002/14651858.CD004307.pub5. [Review search date: December 2014]
    • Subgroup analysis 1.1.5: Smoking cessation in mixed populations - [subgroup: 24 months]
      Risk of bias of studies:

      The reviewers did not perform a GRADE assessment of the quality of evidence for this outcome. Both trials failed to report adequate allocation concealment and random sequence generation, one did not report adequate blinding of participants/carers/outcome assessors and one had unclear numbers of withdrawals.

      Narrative result:

      Two RCTs with 1331 participants found no statistically significant difference between groups.

      Relative effect or mean difference:

      There was a statistically significant difference between groups, in favor of incentives (odds ratio 1.29, 95% CI 0.93 to 1.79).

      Forest plot from Cochrane Review

      Reference:
      Cahill K, Hartmann-Boyce J, Perera R. Incentives for smoking cessation. Cochrane Database of Systematic Reviews 2015, Issue 5. Art. No.: CD004307. DOI: 10.1002/14651858.CD004307.pub5. [Review search date: December 2014]
  • OUTCOME 1.2: Adverse events

    Narrative result:

    The reviewers found no studies assessing this outcome.

    Reference:
    Cahill K, Hartmann-Boyce J, Perera R. Incentives for smoking cessation. Cochrane Database of Systematic Reviews 2015, Issue 5. Art. No.: CD004307. DOI: 10.1002/14651858.CD004307.pub5. [Review search date: December 2014]

    Additional Information:

    DOI

    10.1002/cca.1533

    Publication Dates

    1. Published Online: 30 MAR 2017

    CCA derived from

    Cahill K, Hartmann-Boyce J, Perera R. Incentives for smoking cessation. Cochrane Database of Systematic Reviews 2015, Issue 5. Art. No.: CD004307. DOI: 10.1002/14651858.CD004307.pub5. [Review search date: December 2014]

    How to Cite

    Can providing incentives to stop smoking to adult smokers of mixed populations increase quit rates? Harish Kavirajan (MD) (on behalf of Cochrane Clinical Answers Editors). Cochrane Clinical Answers 2017. DOI: 10.1002/cca.1533.

    Further Information

    • CCA Associate editor: Harish Kavirajan (MD), Assistant Clinical Professor, UCLA David Geffen School of Medicine, CA/Los Angeles, USA.
    • CCA Editor: Karen Pettersen. Correspondence to kpettersen@wiley.com.