Table 2.

Content categories for user description.

Category	Definition
Celebrity	Famous people in pop culture, people that are Internet famous, people that have accounts verified by Twitter
Government	National Institutes of Health, CDC, political figures, etc
Foundation/organization	Reputable organizations such as American Heart Association
Reputable news source	New sources such as New York Times, Washington Post, Wall Street Journal, Associated Press, etc
Everyday person	Twitter account with a reasonable amount of posts, followers, and following a reasonable amount of people; timelines span a variety of topics that are not primarily e-cigarette–related
E-cigarette community movement	Groups or people whose timelines are primarily devoted to e-cigarette conversation (eg, Women Who Vape, The Vape Club, John Doe with entire timeline of e-cigarette tweets)
Retailer	Outlets that sell e-cigarettes (online or physical)
Tobacco company	Companies that manufacture e-cigarettes (eg, blu, Apollo, Njoy)
Bot/hacked	Accounts that appear to be fake/computerized that are primarily promoting e-cigarette products (or other products); most accounts are disguised to appear as “everyday person”