Table A1.

List of Questions Presented to the Study Participants.

Area of Investigation	Questions	Explanation of Measures
Demographic and anthropometric questions (9 items)	What is your age group (in years)? What is your gender? What is your marital status? How many children do you have? What is your education level? What is your district of residence? Are you currently pregnant? What is your weight? What is your height?	7 groups with 10 years range 4 categories 5 categories Range 0–4 and more 4 categories (from less than high school to postgraduate) List of Latvia districts Pregnancy status (yes/no) Kg Cm
COVID-19-related behavioral factors that could increase the risk of infection (15 items)	What is your smoking status? Duration of cigarette smoking When did you quit smoking? Which way of transport do you use? What are your working conditions? Do you comply with social distancing? Do you use face mask? How often do you disinfect your hands? Do you disinfect your hands before touching your face? How much do you worry about COVID-19? What are your living conditions? What is your profession? What are your thoughts about the existing COVID-19 restrictions? Did you in last 14 days travel abroad or visit mass events? What is in your opinion of the percentage of people that follow the official state COVID-19 restrictions?	4 categories Years Years 4 items 7 items Yes/no 3 categories 3 categories 3 categories 3 categories 4 categories of living density 4 categories, increased risk of infection in workplace 3 categories, attitude 4 answers 3 categories (from < 50% to > 80%)
Personal risk factors that could increase the risk of severe disease (10 items)	Do you have chronic diseases?	10 items (yes/no)
Reasons for vaccination (10 items)	Please explain your motivation to vaccinate or not: • Fear of COVID-19 • To protect my family and our relatives • Confidence in our healthcare providers • Confidence in our pharmaceutical industry • The COVID-19 vaccines are revolutionary and use innovative technology • Employer recommends/demands • Confidence in governmental leadership’s guidance • It is my civic responsibility to take this vaccine • Myself or relatives got sick with COVID-19 • Free of charge	Scaled from 1 (completely disagree) to 5 (completely agree)