Summary of findings 2. Acceptance and commitment therapy (ACT) compared with control for smoking cessation.
| Acceptance and commitment therapy (ACT) compared with control for smoking cessation | ||||||
| Patient or population: people who smoke Setting: community; online; primary care; high schools and universities (USA; Cyprus; Hong Kong; Ireland) Intervention: Acceptance and commitment therapy (ACT) Comparisons: matched‐intensity smoking cessation treatment; NRT; brief advice; less intensive ACT | ||||||
| Outcomes | Anticipated absolute effects* (95% CI) | Relative effect (95% CI) | № of participants (studies) | Certainty of the evidence (GRADE) | Comments | |
| Risk with control | Risk with ACT | |||||
| ACT vs matched‐intensity smoking cessation treatment: smoking cessation (≥ 6‐month follow‐up) | It was not appropriate to pool data across these studies because there was a high level of heterogeneity (I2 = 82%) and the result may be misleading. | 5723 (5 RCTs) |
⊕⊝⊝⊝ Very lowa,b,c | |||
| ACT vs NRT: smoking cessation (≥ 6‐month follow‐up) | Study population | RR 1.27 (0.53 to 3.02) | 102 (1 RCT) | ⊕⊕⊝⊝ Lowd | ||
| 15 per 100 | 19 per 100 (8 to 45) | |||||
| ACT vs brief advice: smoking cessation (≥ 6‐month follow‐up) | Study population | RR 1.27 (0.59 to 2.75) | 144 (1 RCT) | ⊕⊝⊝⊝ Very lowd,e | ||
| 14 per 100 | 17 per 100 (8 to 37) | |||||
| ACT vs less intensive ACT: smoking cessation (≥ 6‐month follow‐up) | Study population | RR 1.00 (0.50 to 2.01) | 100 (1 RCT) | ⊕⊕⊝⊝ Lowd | ||
| 24 per 100 | 24 per 100 (12 to 48) | |||||
| Mental health and well‐being | One study that compared ACT with NRT found no clinically meaningful difference in negative affect across conditions at all follow‐ups to 12 months. Another study that compared ACT with a matched‐intensity smoking cessation treatment and a less intensive ACT intervention found no clinically meaningful difference in positive mental health across conditions up to 6‐month follow‐up. |
252 (2 RCTs) |
⊕⊝⊝⊝ Very lowf,g | We were unable to meta‐analyse this outcome and therefore summarised narratively. | ||
| *The risk in the intervention group (and its 95% confidence interval) is based on the assumed risk in the comparison group and the relative effect of the intervention (and its 95% CI). ACT: Acceptance and commitment therapy; CI: confidence interval; NRT: nicotine replacement therapy; RCT: randomised controlled trial; RR: risk ratio | ||||||
| GRADE Working Group grades of evidence High certainty: we are very confident that the true effect lies close to that of the estimate of the effect. Moderate certainty: we are moderately confident in the effect estimate: the true effect is likely to be close to the estimate of the effect, but there is a possibility that it is substantially different. Low certainty: our confidence in the effect estimate is limited: the true effect may be substantially different from the estimate of the effect. Very low certainty: we have very little confidence in the effect estimate: the true effect is likely to be substantially different from the estimate of effect. | ||||||
aDowngraded by two levels due to inconsistency: substantial heterogeneity was detected (I² = 82%). A subgroup analysis grouping by mode of delivery used explained a small amount of this, but substantial heterogeneity remained unexplained. bNot downgraded for indirectness. One study included only smokers without health insurance, but contributed just 17.3% of the weighted effect. cDowngraded by one level due to imprecision: the confidence interval of the effect estimate incorporates clinically relevant potential benefit and harm of the intervention. dDowngraded by two levels due to imprecision: the overall number of events was very low (< 25) and the confidence interval of the effect estimate incorporates clinically relevant potential benefit and harm of the intervention. eDowngraded by two levels due to risk of bias: we judged the sole study to be at high risk of bias. fDowngraded by two levels due to inconsistency: the constructs and measures of mental health used differed across studies, as well as the study comparators. gDowngraded by two levels due to imprecision: two small studies likely lacked sufficient statistical power to detect clinically meaningful effects.