Table 2.

Inclusion and exclusion criteria for literature

Criteria	Included	Excluded
Population	All residents or a population subgroup (e.g., students). Populations need not be humans (e.g., vape shops, manufacturers).	No restrictions
Intervention	Any regulations enacted by national/local governments to regulate the production, marketing, or sales of ENPs.	Any regulations not enacted by governments or their agencies, such as school and prison vape-free policies
Comparator	With at least one comparison or control period or group	Without a control or comparison group
Outcome measures	Studies focused on the prevalence of electronic nicotine product use (use ENPs at least once in the past 30-days), related illnesses and injuries [32], and any factors that may influence ENP use or associated injuries, such as sales, perceptions, exposure to marketing, and quality of e-liquid.	Studies focused on the unintended effects of e-cigarette policies, such as cigarette smoking rates and substance use.
Type of study	Empirical studies with pre-post and quasi-experimental designs (defined in Table S2 in the Online Supplementary Document), including interrupted time series (ITS), differences-in-differences (DID), synthetic control (SC), instrumental variables (IV) and regression discontinuity (RD) designs.	Non-empirical studies and cross-sectional studies
Type of publication	Peer-reviewed articles	Other types of publication, for example, editorials, comments.

ENP – electronic nicotine product