Background: The workplace has potential as a setting through which large groups of people can be reached to encourage smoking cessation.
Objectives: To categorize workplace interventions for smoking cessation tested in controlled studies and to determine the extent to which they help workers to stop smoking or to reduce tobacco consumption.
Search strategy: We searched the Cochrane Tobacco Addiction Group Specialized Register in April 2008, MEDLINE (1966 - April 2008), EMBASE (1985 - Feb 2008) and PsycINFO (to March 2008). We searched abstracts from international conferences on tobacco and the bibliographies of identified studies and reviews for additional references.
Selection criteria: We selected interventions conducted in the workplace to promote smoking cessation. We included only randomized and quasi-randomized controlled trials allocating individuals, workplaces or companies to intervention or control conditions.
Data collection and analysis: Information relating to the characteristics and content of all kinds of interventions, participants, outcomes and methods of the study was abstracted by one author and checked by another. Because of heterogeneity in the design and content of the included studies, we did not attempt formal meta-analysis, and evaluated the studies using qualitative narrative synthesis.
Main results: We include 51 studies covering 53 interventions in this updated review. We found 37 studies of workplace interventions aimed at individual workers, covering group therapy, individual counselling, self-help materials, nicotine replacement therapy and social support. The results were consistent with those found in other settings. Group programmes, individual counselling and nicotine replacement therapy increased cessation rates in comparison to no treatment or minimal intervention controls. Self-help materials were less effective. We also found 16 studies testing interventions applied to the workplace as a whole. There was a lack of evidence that comprehensive programmes reduced the prevalence of smoking. Incentive schemes increased attempts to stop smoking, though there was less evidence that they increased the rate of actual quitting.
Authors' conclusions: 1. We found strong evidence that interventions directed towards individual smokers increase the likelihood of quitting smoking. These include individual and group counselling and pharmacological treatment to overcome nicotine addiction. All these interventions show similar effects whether offered in the workplace or elsewhere. Self-help interventions and social support are less effective. Although people taking up these interventions are more likely to stop, the absolute numbers who quit are low.2. There was limited evidence that participation in programmes can be increased by competitions and incentives organized by the employer.3. We failed to detect an effect of comprehensive programmes in reducing the prevalence of smoking.