Table 1.

Description of the characteristics of the studies

Author, year	Location	Acronym	Recruitment	Baseline year	Follow-up (months)	Loss at follow-up	Covariatesa	Risk of bias
Everard et al.18 2020	USA	PATH	National cohort with non-institutionalized adults (≥18 years old)	2013–2014	36	NI	Age, sex, race/ethnicity, education, family income, use of other tobacco products, internalizing/externalizing/substance use problems and past cigarette use behavior	Moderate
McMillen et al.20 2019	USA	PATH	National cohort with non-institutionalized adults (≥18 years old)	2013–2014	12	16.9%	Age, sex, race/ethnicity, education, household smoking rules and cohabitation with smokers	High
Verplaetse et al.21 2019	USA	PATH	National cohort with non-institutionalized adults (≥18 years old)	2013–2014	12	NI	Age, sex, race/ethnicity and education	High
Brose et al.22 2019*	UK	-	National general population sample of smokers, former smokers and vapers (≥18 years old)	2016	16	48.4%	Age, sex, annual income, duration of cessation, use of NRT and characteristics of e-cigarette use	Moderate
Dai et al.19 2019*	USA	PATH	National cohort with non-institutionalized adults (≥18 years old)	2013–2014	12	16.9%	Age, sex, race/ethnicity, education, family income, health insurance and region	Low
Gomajee et al.16 2019*	France	CONSTANCES	National sample of adults (18–69 years old) from a compulsory health insurance (85% of population coverage)	2015	22 (mean)	1.0%	Age, sex, marital status, education, income, use of alcohol, number of cigarettes smoked at baseline, number of packs/year, duration of previous attempts to quit and comorbidities (depression, respiratory disorders)	Low

PATH: Population Assessment of Tobacco and Health Study. NRT: nicotine replacement therapy. NI: not informed.

^*Included in the quantitative synthesis (meta-analysis).

^aIncluded in the multivariate model of the original study