The primary objective of this review is to determine the effectiveness of smoking reduction and cessation interventions (alone, or in combination with other interventions), delivered primarily in an outpatient or community-based setting among individuals with mental disorders, on rates of abstinence at the longest follow-up (minimum six months), mental health symptoms and adverse events.

Secondary objectives are to examine the impact of such interventions on rates of abstinence at the end of the intervention, change in daily cigarette consumption, and quality-of-life or other function scores. We will explore (via subgroup analyses) potential differential effects on the basis of intervention type, control group type, recruitment setting (inpatient versus outpatient), mental disorder type, and motivation to quit at study intake.

We may come across studies testing interventions which aim to increase the uptake of smoking interventions in people with a mental disorder. This may comprise interventions that either are incorporated into the system of delivering care, aimed at health professionals (e.g. within a community mental health facility), as well as interventions aimed directly at people with a mental disorder to increase uptake. In this case we aim to examine whether these interventions increase the uptake of the smoking cessation treatment among people with a mental disorder, as well as whether they ultimately result in increased quit rates.