Characteristics of the eligible seroprevalence studies
| Location (reference) | Type of population | Date | Sample tested, n | Age cut-off,* y |
| Europe | ||||
| Denmark (17) | Blood donors | 1–26 June | 2311 | 70 |
| Hungary (18) | General | 1–16 May | 10 472 | 65 |
| Iceland (19) | General | April–June | 30 576 | 70 |
| Spain (20) | General | 14 April to 1 May | 61 075 | 65 |
| UK (21) | General | 20 June to 13 July | 99 908 | 65 |
| UK (22) | Biobank | 27 May to 14 August | 18 734 | 70 |
| Americas | ||||
| Brazil (23) | General | 4–7 June | 31 165 | 70 |
| Canada (24) | Blood donors | May | 37 737 | 60 |
| Dominican Republic(25) | General, hotspot areas | April–June | 12 897 | 60 |
| USA (26) | Haemodialysis | July | 28 503 | 65 |
| USA (27) | Life insurance applicants | 12 May to 25 June | 50 025 | 61 |
| USA (28) | Blood donors | June–July | 189 656 | 65 |
| USA—New York (29) | General, convenience | 19–28 April | 15 101 | 55 |
| USA—Brooklyn (30) | General, convenience | Early May | 11 092 | 70 |
| Asia | ||||
| China—Wuchang (31) | General | Mid-May | 61 437 | 70 |
| China (32) | Diverse | January–April | 17 368 | 65 |
| India (33) | General | 11 May to 4 June | 28 000 | 60 |
*For the comparison of seroprevalence in elderly versus younger participants, 70 years was the default cut-off chosen, but as shown in this column, a lower cut-off was chosen when seroprevalence data according to the 70-year cut-off were not available.