Table 1.

Population, Intervention, Comparison, Outcome (PICO) tool

PICO	Description	Search terms and connectors
Population	Individuals from socioeconomically deprived groups, defined through either individual or area level indicators	(Depriv* or disadvantage* or inequit* or socioeconomic or socio-economic or sociodemographic or socio-demographic or social class or deprivation group or poverty or low income or social welfare).tw.
Intervention	A range of interventions including individual and group counselling, self-help materials, pharmacological interventions (eg, nicotine replacement therapy), social and environmental support, comprehensive programmes and incentives	Smoking Cessation/ and (intervention* or initiative* or strategy* or program* or scheme* or outcome* or approach*).tw.
Comparison	All study types with a pre-intervention/post-intervention and/or a control group	–
Outcome	Primary outcome: smoking abstinence Secondary outcome: moderating variables (eg, nicotine dependence, quit motivation, self-efficacy, social support and influences)	((nicotine or tobacco or smok* or cigarette) adj (quit* or stop* or cess* or cease* or cut down or “giv* up” or reduc*)).tw.