Measure	Coding/Scoring
Smoking and quitting behavior
Changes in amount of cigarette smoking	“How has your cigarette use changed since February 2020 (the start of the COVID-19 pandemic)?” [Increased use, use stayed the same [mode, reference category], decreased use]
Readiness to quit smoking	“Select the number that indicates where you are now in your thinking about quitting smoking.” [No thought of quitting (0) through I am now taking action to quit (10)] Scale collapsed into three categories for analysis: 0–2 vs. 3–7 vs. 8–10.
Quit attempts	“Since February 2020 (the start of the COVID-19 pandemic), have you ever made a serious attempt to quit smoking? That is, have you stopped smoking for at least one day or longer because you were trying to quit?” [Yes, No [mode, reference category]]
COVID-19 risk perceptions
Smoking-related susceptibility to COVID-19	“Based on what you believe, how much do you agree or disagree with the following statements? Smoking cigarettes can cause me to be more likely to get coronavirus.” [strongly disagree/disagree, neither disagree nor agree [mode, reference category], agree/strongly agree]
Smoking-related severity of COVID-19 effects	“Based on what you believe, how much do you agree or disagree with the following statements? Smoking cigarettes can cause me to have more severe effects of coronavirus.” [strongly disagree/disagree, neither disagree nor agree [mode, reference category], agree/strongly agree]
General susceptibility to COVID-19	“How likely do you think you are to be infected by the coronavirus over the next year?” [Unlikely (1), possible (2), likely (3), almost certain (4), certain (5)]
General severity of COVID-19 symptoms	“On a scale from 0 to 10, how severe do you think your symptoms will be if you become infected with coronavirus?” [I would likely have no symptoms (0) to I would likely die from it (10)]
Participant characteristics and other covariates
SexGender	Male, Female
Age	18–29, 30–44, 45–59, 60+
Race/ethnicity	White non-Hispanic, Black non-Hispanic, Other non-Hispanic, Hispanic
Education	Less than High school, High school graduate, Some college, Bachelor’s degree or higher
Household income	< $30,000, $30,000 - $99,999, ≥ $100,000
ENDS use status	Current user, Recent quitter (quit since Feb 2020), Never use or quit before Feb 2020
Psychological distress	“During the past 30 days, about how often did you feel: 1. Nervous 2. Hopeless 3. Restless or fidgety 4. So depressed that nothing could cheer you up 5. That everything was an effort 6. Worthless” [All of the time (4), Most of the time (3), Some of the time (2), A little of the time (1), None of the time (0)] Responses were summed for a range of 0 to 24.
Self-efficacy for quitting smoking	“If you decided you wanted to quit smoking and never start again, how easy or hard do you think it would be for you to do?” [Very easy (1), Hard but you could do it if you tried (2), Very difficult and you might not be able to do it (3), Almost impossible (4)]
Nicotine dependence	“Please rate how often each of the following statements applies to you. 1. I find myself reaching for cigarettes without thinking about it. 2. I drop everything to go out and buy cigarettes. 3. When I haven’t been able to smoke for a few hours, the craving gets intolerable. 4. I smoke more before going into a situation where smoking is not allowed.” [Never (1), Rarely (2), Sometimes (3), Often (4), Always (5)] Responses were summed for a range of 4 to 20.
Cigarettes harder to obtain	“Since February 2020, cigarettes have been… [Easier to obtain (1), Neither easier nor more difficult to obtain (2), More difficult to obtain (3)]”
Cigarettes less affordable	“Since February 2020, cigarettes have been… [More affordable (1), Neither more nor less affordable (2), Less affordable (3)]”
Time spent in places where smoking is allowed	“Since February 2020, what has changed about the amount of time you spend in places or situations where cigarette smoking is allowed?” [I spend more time in places or situations where cigarette smoking is allowed (1), No change (2), I spend less time in places or situations where cigarette smoking is allowed (3)]