From: Data collection in pandemic times: the case of the Belgian COVID-19 health surveys
 | Survey 1 - Beginning of April 2020 (n=49334) | Survey 2 - End of April 2020 (n=42895) | Survey 3 - May 2020 (n=33913) | Survey 4 - September 2020 (n=30845) | Survey 5 - December 2020 (n=29855) | Survey 6 - March 2021 (n=20410) | Survey 7 - June 2021 (n=17774) | Survey 8 - October 2021 (n=17347) | Survey 9 - December 2021 (n=22354) | Survey 10 - March 2022 (n=13882) | Cohort (n = 12599)a | Population distribution 2020b,c |
---|---|---|---|---|---|---|---|---|---|---|---|---|
 | % | % | % | % | % | % | % | % | % | % | % | % |
Sex | ||||||||||||
 Men | 31.8 | 31.6 | 34.9 | 36.5 | 38.7 | 35.6 | 35.8 | 36.2 | 36.5 | 36.0 | 35.8 | 48.8 |
 Women | 68.2 | 68.4 | 65.1 | 63.5 | 61.3 | 64.4 | 64.2 | 62.8 | 63.5 | 64.0 | 64.1 | 51.2 |
Age group | ||||||||||||
 18-24 | 5.3 | 3.3 | 3.3 | 2.3 | 2.5 | 1.7 | 3.3 | 5.8 | 4.6 | 2.8 | 1.0 | 10.1 |
 25-34 | 19.7 | 15.7 | 14.2 | 12.4 | 11.9 | 9.8 | 10.6 | 9.3 | 10.3 | 7.9 | 8.5 | 16.2 |
 35-44 | 24.4 | 22.6 | 20.3 | 20.4 | 19.3 | 17.9 | 16.6 | 15.5 | 18.4 | 14.1 | 16.4 | 16.2 |
 45-54 | 21.2 | 22.9 | 21.1 | 21.9 | 20.9 | 20.8 | 20.0 | 19.5 | 20.6 | 19.6 | 20.5 | 17.0 |
 55-64 | 18.1 | 21.4 | 23.0 | 23.7 | 24.6 | 24.4 | 24.7 | 24.3 | 23.3 | 25.4 | 26.1 | 16.6 |
 65-74 | 9.5 | 11.9 | 15.6 | 16.5 | 17.9 | 21.2 | 20.6 | 21.0 | 19.2 | 24.2 | 23.0 | 12.7 |
 75+ | 1.8 | 2.2 | 2.6 | 2.9 | 3.0 | 4.1 | 4.3 | 4.6 | 3.6 | 6.2 | 4.5 | 11.3 |
Highest diploma | ||||||||||||
 Secondary diploma or less | 27.6 | 26.8 | 25.2 | 25.3 | 24.4 | 24.8 | 25.5 | 27.7 | 27.5 | 26.1 | 25.3 | 58.9 |
 Higher education | 69.4 | 69.8 | 71.5 | 71.9 | 72.9 | 72.6 | 72.1 | 70.0 | 69.8 | 71.5 | 74.7 | 41.1 |
Region | ||||||||||||
 Flemish Region | 64.5 | 50.8 | 67.8 | 68.5 | 69.3 | 65.4 | 64.5 | 64.6 | 65.0 | 65.7 | 63.1 | 58.2 |
 Brussels Capital Region | 9.9 | 11.3 | 8.4 | 9.3 | 8.9 | 9.9 | 9.1 | 9.3 | 8.7 | 9.3 | 9.9 | 10.3 |
 Walloon Region | 25.7 | 37.9 | 23.8 | 22.2 | 21.8 | 24.7 | 26.4 | 26.0 | 26.3 | 25.0 | 26.7 | 31.6 |