| Measurement items | Reference |
|---|---|
| Optimistic biasa | Modified from Otten and van der Pligt's study16 |
| (“Self” dimension) “What do you believe is the chance that you will get infected by COVID-19 (coronavirus)?” | |
| (“others” dimension) “I would like you to think of people your own age and sex. What do you believe is the chance that the average person your age and sex will get infected by COVID-19 (coronavirus)?” | |
| Risk perceptionb | Modified from So et al.’s and Witte's studies18,19 |
| Perceived susceptibility | |
| I believe I'm at risk for contracting COVID-19 (coronavirus). | |
| It's likely that I will contract COVID-19 (coronavirus). | |
| It is possible that I will contract COVID-19 (coronavirus). | |
| Perceived severity | |
| I believe that COVID-19 (coronavirus) is a severe health problem. | |
| I believe that COVID-19 (coronavirus) is a deadly virus. | |
| Risk responseb | Modified from So et al.’s, Spielberger et al.’s, and Fioravanti-Bastos et al.’s studies18,20,21 |
| Anxiety | |
| I am worried about COVID-19 (coronavirus). | |
| I feel nervous about COVID-19 (coronavirus). | |
| I feel tense about COVID-19 (coronavirus). | |
| I feel confused about COVID-19 (coronavirus). | |
| I am relaxed about COVID-19 (coronavirus). | |
| I feel calm about COVID-19 (coronavirus). | |
| Fear | Modified from So et al.’s and Dillard and Peck's studies18,22 |
| I am afraid of COVID-19 (coronavirus). | |
| I am frightened by COVID-19 (coronavirus). | |
| I am scared of COVID-19 (coronavirus). | |
| Behavioral outcomesc | Modified from Lee et al.’s study23 |
| “After seeing, reading, or hearing about COVID-19 (coronavirus), have you done any of the following in the past couple of months?” | |
| I have talked with my doctor about COVID-19 (coronavirus) risk and prevention. | |
| I have talked with my pharmacist about COVID-19 (coronavirus) risk and prevention. | |
| I have talked with my family members, friends, or relatives about COVID-19 (coronavirus) risk and prevention. | |
| I have talked with my coworkers about COVID-19 (coronavirus) risk and prevention. | |
| Information seeking intentionsd | Modified from Hovick et al.’s study24 |
| How likely are you to directly seek information from clinical interpersonal sources (e.g., doctors, pharmacists, and other medical professionals) about COVID-19 (coronavirus) risk and prevention? | |
| How likely are you to consult clinical interpersonal sources (e.g., doctors, pharmacists, and other medical professionals) for information about COVID-19 (coronavirus) risk and prevention? | |
| How likely are you to gather information from clinical interpersonal sources (e.g., doctors, pharmacists, and other medical professionals) about COVID-19 (coronavirus) risk and prevention? | |
| How likely are you to directly seek information from non-clinical interpersonal sources (e.g., family members, friends, relatives, and coworkers) about COVID-19 (coronavirus) risk and prevention? | |
| How likely are you to consult non-clinical interpersonal sources (e.g., family members, friends, relatives, and coworkers) for information about COVID-19 (coronavirus) risk and prevention? | |
| How likely are you to gather information from non-clinical interpersonal sources (e.g., family members, friends, relatives, and coworkers) about COVID-19 (coronavirus) risk and prevention? |
a Scale: 0 = no chance, …, 5 = 50-50 chance, …, 10 = certain to happen.
b Scale: 1 = strongly disagree, …, 4 = neither disagree nor agree, …, 7 = strongly agree.
c Scale: 1 = never, 2 = rarely, 3 = sometimes, 4 = often, 5 = very often.
d Scale: 1 = extremely unlikely, …, 4 = neither unlikely nor likely, …, 7 = extremely likely.