What do systematic reviews say?

Reduction and pharmacotherapy vs reduction alone

Reduction and pharmacotherapy probably leads to higher subgroup: varenicline only; smoking cessation (≥ 6 month compared with reduction alone (moderate certainty).

• Smoking reduction interventions for smoking cessation 2019 · Cochrane Headline outcomes only
  RR 3.99 [2.93, 5.44]
  1 study · 1510 participants
  Moderate

Reduction and pharmacotherapy vs reduction alone

Reduction and pharmacotherapy showed no clear difference in subgroup: bupropion only; smoking cessation (≥ 6 month compared with reduction alone (low certainty).

• Smoking reduction interventions for smoking cessation 2019 · Cochrane Headline outcomes only
  RR 1.27 [0.67, 2.4]
  1 study · 594 participants
  Low

Intervention not reported

• Mass media interventions for preventing smoking in young people 2017 · Cochrane Headline outcomes only
  no estimate extracted
  8 studies · 90125 participants
  Very low

Intervention not reported

The intervention probably leads to higher smoking cessation at longest (moderate certainty).

• Nursing interventions for smoking cessation 2017 · Cochrane Headline outcomes only
  RR 1.29 [1.21, 1.38]
  44 studies · 20881 participants
  Moderate

Intervention not reported

The intervention probably leads to higher smoking cessation at longest (moderate certainty).

• Nursing interventions for smoking cessation 2017 · Cochrane Headline outcomes only
  RR 1.29 [1.21, 1.38]
  37 studies · 16865 participants
  Moderate

Intervention not reported

The intervention showed no clear difference in smoking cessation at longest (moderate certainty).

• Nursing interventions for smoking cessation 2017 · Cochrane Headline outcomes only
  RR 1.27 [0.99, 1.62]
  7 studies · 4016 participants
  Moderate

Intervention not reported

• Mass media interventions for smoking cessation in adults 2017 · Cochrane Headline outcomes only
  no estimate extracted
  Studies not reported
  Very low

Intervention not reported

• Mass media interventions for smoking cessation in adults 2017 · Cochrane Headline outcomes only
  no estimate extracted
  Studies not reported
  Very low

Intervention not reported

• Mass media interventions for smoking cessation in adults 2017 · Cochrane Headline outcomes only
  no estimate extracted
  Studies not reported
  Very low

Intervention not reported

• Mass media interventions for smoking cessation in adults 2017 · Cochrane Headline outcomes only
  no estimate extracted
  Studies not reported
  Very low

Intervention not reported

The review found no eligible studies for this question.

• Internet‐based interventions for smoking cessation 2017 · Cochrane Headline outcomes only
  no estimate extracted
  Studies not reported
  No studies found

Intervention not reported

The intervention may leads to higher interactive and tailored versus non‐active control Self‐report or… (low certainty).

• Internet‐based interventions for smoking cessation 2017 · Cochrane Headline outcomes only
  RR 1.15 [1.01, 1.3]
  8 studies · 6786 participants
  Low

Intervention not reported

The intervention showed no clear difference in internet versus active control Self‐report or bio‐verified smoking… (moderate certainty).

• Internet‐based interventions for smoking cessation 2017 · Cochrane Headline outcomes only
  RR 0.92 [0.78, 1.09]
  5 studies · 3806 participants
  Moderate

Intervention not reported

The intervention probably leads to higher internet plus behavioural support versus non‐Internet‐based… (moderate certainty).

• Internet‐based interventions for smoking cessation 2017 · Cochrane Headline outcomes only
  RR 1.69 [1.3, 2.18]
  5 studies · 2334 participants
  Moderate

Intervention not reported

The intervention showed no clear difference in internet plus behavioural support versus non‐Internet‐based active… (moderate certainty).

• Internet‐based interventions for smoking cessation 2017 · Cochrane Headline outcomes only
  RR 1 [0.84, 1.18]
  4 studies · 2769 participants
  Moderate

Intervention not reported

• System change interventions for smoking cessation 2017 · Cochrane Headline outcomes only
  no estimate extracted
  4 studies · 7142 participants
  Very low

Intervention not reported

• System change interventions for smoking cessation 2017 · Cochrane Headline outcomes only
  no estimate extracted
  4 studies · 10949 participants
  Low

Intervention not reported

• System change interventions for smoking cessation 2017 · Cochrane Headline outcomes only
  no estimate extracted
  3 studies · 2615 participants
  Low

Intervention not reported

• System change interventions for smoking cessation 2017 · Cochrane Headline outcomes only
  no estimate extracted
  3 studies · 3003 participants
  Low

Intervention not reported

• System change interventions for smoking cessation 2017 · Cochrane Headline outcomes only
  no estimate extracted
  3 studies · 3006 participants
  Very low