Table 1.

Study variables.

Item	Response options	Year(s) of survey data
1. Age	1. 18–24 years	2021, 2022, 2023
	2. 25–54 years
	3. 55–64 years
	4. 65 years or older
2. Gender	1. Male	2021, 2022, 2023
	2. Female
	3. Prefer not to say
	4. Other
3. Education	1. Less than High School	2021, 2022, 2023
	2. High School degree or GED
	3. Some College
	4. Associate or Vocational degree
	5. Bachelor Degree
	6. Post-Graduate Degree (Master's, Lawyer, Doctor)
4. Income	1. My monthly income is more than [Country median calculated from World Bank Data]	2021, 2022, 2023
	2. My monthly income is less than [Country median calculated from World Bank Data].
	3. I do not have an income.
	4. Refused/ Did not answer
5. Race/Ethnicity	1. Hispanic or Latino of any race	2021, 2022, 2023
	2. White or Caucasian
	3. Black or African American
	4. Asian
	5. Other or multiple races
6. Statistical Region	1. Northeast	2021, 2022, 2023
	2. South
	3. Midwest
	4. West
7. Have you received at least one dose of a COVID-19 vaccine?	1. Yes, I received one dose	2023
	2. Yes, I received two or more doses
	3. No
8. Have you received at least one dose of a COVID-19 vaccine?	1. Yes, partially vaccinated	2022
	2. Yes, completely vaccinated
	3. Yes, completely and received at least one booster dose
9. Have you received at least one dose of a COVID-19 vaccine?	1. Yes	2021
	2. No
10.    Have you lost a family member or close friend to COVID-19 disease?	1. Yes, within the past year	2022, 2023
	2. Yes, more than a year ago
	3. No
11.    Have you lost a family member to COVID-19 disease?	1. Yes	2021
	2. No
12.    How much do you trust the following sources of information about COVID-19 vaccines: the Centers for Disease Control and Prevention.	1 (trust completely) to	2023
	10 (do not trust at all)
13.    I trust the science behind the COVID-19 vaccines.	1.      Strongly disagree	2021, 2022, 2023
	2.      Disagree
	3.      Neutral/Unsure
	4.      Agree
	5.      Strongly agree

Legend: None.