Table 1.
Characteristics of included studies (n = 97).
| Variables | n (%) |
|---|---|
| Year of study | |
| 2019 | 0 (0) |
| 2020 | 48 (49.5) |
| 2021 | 49 (50.5) |
| Continent of study | |
| North America | 42 (43.3) |
| Europe | 33 (34) |
| Asia | 11 (11.3) |
| Oceania | 7 (7.2) |
| Cross-continents | 4 (4.1) |
| Country of study | |
| USA | 39 (40.2) |
| Italy | 9 (9.3) |
| Multiple countries | 9 (9.3) |
| Australia | 6 (6.2) |
| France | 6 (6.2) |
| Hong Kong | 4 (4.1) |
| U.K. | 8 (8.2) |
| Germany | 2 (2.1) |
| Poland | 2 (2.1) |
| UAE | 2 (2.1) |
| Canada | 2 (2.1) |
| Other countries a | 8 (8.2) |
| Patient populations | |
| General public | 71 (73.2) |
| Healthcare workers | 13 (13.4) |
| University students and/or university staff | 5 (5.2) |
| Patients with autoimmune conditions | 3 (3.1) |
| Patients with malignancy | 1 (1) |
| Adolescents and/or children | 1 (1) |
| Others b | 3 (3.1) |
| Number of study participants | |
| 0–1000 | 28 (28.9) |
| 1001–2000 | 32 (33) |
| 2001–5000 | 25 (25.8) |
| 5001–10,000 | 11 (11.3) |
| >10,000 | 1 (1) |
| Study design | |
| Cross-sectional study | 75 (77.3) |
| Mixed methods | 14 (14.4) |
| Randomized controlled trials | 2 (2.1) |
| Pure qualitative study | 1 (1) |
| Case control study | 2 (2.1) |
| Longitudinal study | 3 (3.1) |
| Methodology of data collection # | |
| Online survey | 87 (89.7) |
| Telephone interview | 7 (7.2) |
| Paper questionnaire | 3 (3.1) |
| Face-to-face survey | 2 (2.1) |
| Focus group discussion | 2 (2.1) |
| Combinations of methods c | 5 (5.2) |
| Response rates | |
| 0–<25% | 5 (5.2) |
| 25–<50% | 7 (7.2) |
| 50–<75% | 15 (15.5) |
| 75–100% | 17 (17.5) |
| Not specified | 53 (54.6) |
| Use of validated questionnaire | |
| Yes | 26 (26.8) |
| No | 71 (73.2) |
| COVID-19 vaccine hesitancy 30% or more across continents d,e | |
| North America | 25/42 (59.5) |
| Europe | 11/33 (33.3) |
| Asia | 8/11 (72.7) |
| Oceania | 2/7 (28.6) |
a Finland (n = 1), Greece (n = 1), Israel (n = 1), Japan (n = 1), Kuwait (n = 1), New Zealand (n = 1), Qatar (n = 1), Saudi Arabia (n = 1). b Parents/caregivers (n = 1), firefighters / first responders (n = 1), Blacks living with HIV (n = 1). c Studies using a combination of either of online, face to face, paper questionnaire, telephone or mail methods included. d Studies involving participants from multi-continents (n = 4) are omitted in the table. e Studies reporting guardians’ vaccine hesitancy for their wards included in the analysis (if a study reports both guardians’ hesitancy for wards and for themselves, the higher of the 2 is taken into consideration for count here). # Each category has been reported as per described in individual study and the net total will be more than 97 due to some studies having combination methods.