Table 2.
Evidentiary Basis for Strong Recommendation Favoring Varenicline over Bupropion with Moderate-Certainty Evidence
| Certainty Assessment |
Number (or Percent) |
Effect (95% CI) |
Certainty | Importance | ||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| No. of Studies | Study Design | Risk of Bias | Inconsistency | Indirectness | Imprecision | Other Considerations | Varenicline | Bupropion | Relative | Absolute (per 1,000 Patients) | ||
|
Seven-day point-prevalence tobacco abstinence at 6 mo (follow-up: 6 mo; assessed with self-report + exhaled carbon-monoxide concentration verification) | ||||||||||||
| 4 | RCT | Not serious | Not serious | Not serious | Not serious | None | 874/2,819 (31.0%) | 25.6% | RR, 1.30 (1.19–1.42) | 77 more (↑49–↑108) | High | Critical |
|
Seven-day point-prevalence tobacco abstinence during treatment period (follow-up: range, 8–12 wk; assessed with self-report + exhaled carbon-monoxide concentration verification) | ||||||||||||
| 5 | RCT | Not serious | Not serious | Not serious | Not serious | None | 1,206/2,834 (42.6%) | 35.9% | RR, 1.41 (1.32–1.52) | 147 more (↑115–↑187) | High | Critical |
|
Quality of life, self-control (follow-up: 12 mo; assessed with smoking-cessation quality of life; higher score indicates better outcome) | ||||||||||||
| 2 | RCT | Serious | Not serious | Not serious | Serious | None | 448 | 398 | — | Effect size, 0.17 | Low | Critical |
|
Quality of life, health transition (follow-up: 12 mo; assessed with smoking-cessation quality of life; lower score indicates better outcome) | ||||||||||||
| 2 | RCT | Serious | Not serious | Not serious | Serious | None | 451 | 401 | — | Effect size, −0.18 | Low | Critical |
|
Serious adverse events (follow-up: range, 7 wk to 3 mo) | ||||||||||||
| 7 | RCT | Not serious | Not serious | Not serious | Serious | None | 54/2,954 (1.8%) | 1.8% | RR, 0.81 (0.57–1.16) | 3 fewer (↓8–↑3) | Moderate | Critical |
|
Tobacco-use relapse measured at the end of follow-up, not measured | ||||||||||||
| — | — | — | — | — | — | — | — | — | — | — | — | — |
|
Other substance abuse, not measured | ||||||||||||
| — | — | — | — | — | — | — | — | — | — | — | — | — |
|
Withdrawal symptom, urge to smoke (follow-up: 12 wk; assessed with MNWS; lower score indicates better outcome; scale of 0–4) | ||||||||||||
| 3 | RCT | Not serious | Not serious | Not serious | Serious | None | 798 | 772 | — | MD, 0.3 lower (↓0.43–↓0.17) | Moderate | Critical |
|
Withdrawal symptom, QSU-brief total craving score (follow-up: 12 wk; assessed with QSU-brief; lower score indicates better outcome) | ||||||||||||
| 3 | RCT | Not serious | Not serious | Not serious | Serious | None | 797 | 772 | — | MD, 0.23 lower (↓0.37–↓0.09) | Moderate | Critical |
Definition of abbreviations: ↑ = increase of; ↓ = decrease of; CI = confidence interval; MD = mean difference; MNWS = Minnesota Nicotine Withdrawal Scale; QSU-brief = Brief Questionnaire of Smoking Urges; RCT = randomized controlled trial; RR = relative risk.
Varenicline treatment showed significant benefit compared with bupropion and showed similar risk of harm. For complete evidence tables, together with references, explanations of certainty assessments, and results of the Evidence-to-Decision process, see online supplement.