Table 2.
Characteristics of respondents and non-respondents to the COVID-19 questionnaires.
| Variable | Respondents | Non-respondents | P-value | Total |
|---|---|---|---|---|
| Number of observations, (%) | 72,098 (53.63) | 62,336 (46.37) | 134,434 | |
| Number of depression symptoms before COVID-19, mean (sd) | 0.25 (1.11) | 0.32 (1.26) | P < 0.0001 | 0.27 (1.17) |
| Major depressive disorder before COVID-19, % | 2.54 | 3.38 | P < 0.0001 | 2.83 |
| Number of anxiety symptoms before COVID-19, mean (sd) | 0.30 (1.24) | 0.36 (1.37) | P < 0.0001 | 0.32 (1.28) |
| Generalized anxiety disorder before COVID-19, % | 4.95 | 5.98 | P < 0.0001 | 5.31 |
| Self-rated health (1 = excellent, … , 5 = bad), mean (sd) | 2.63 (0.80) | 2.70 (0.80) | P < 0.0001 | 2.66 (0.80) |
| Men, % | 39.31 | 43.99 | P < 0.0001 | 41.48 |
| Current age, mean (sd) | 56.57 (12.19) | 50.76 (12.27) | P < 0.0001 | 55.22 (12.50) |
| Marital status at last visit, % | ||||
| Married | 66.53 | 61.89 | P < 0.0001 | 64.87 |
| Registered partner- ship | 16.54 | 20.24 | P < 0.0001 | 17.86 |
| In relationship but living apart | 4.94 | 5.60 | P < 0.0001 | 5.18 |
| Single | 11.09 | 11.30 | P = 0.3409 | 11.16 |
| Other | 0.90 | 0.97 | P = 0.3697 | 0.93 |
| BMI at last visit, mean (sd) | 26.08 (4.25) | 26.11 (4.26) | P = 0.4750 | 26.09 (4.25) |
| Smoking at last visit, % | ||||
| Never | 46.52 | 47.06 | P = 0.1686 | 46.68 |
| Ex | 40.02 | 34.18 | P < 0.0001 | 38.30 |
| Current | 13.46 | 18.75 | P < 0.0001 | 15.06 |
| Number of people in household, mean (sd) | 2.76 (1.23) | 3.03 (1.30) | P < 0.0001 | 2.85 (1.26) |
| Highest education at last visit, % | ||||
| None | 0.29 | 0.65 | P < 0.0001 | 0.42 |
| Primary | 0.92 | 1.62 | P < 0.0001 | 1.17 |
| Lower or preparatory secondary vocational | 10.84 | 13.74 | P < 0.0001 | 11.88 |
| Junior general secondary | 14.13 | 13.54 | P = 0.0180 | 13.92 |
| Secondary vocational or work-based learning pathway | 28.53 | 31.44 | P < 0.0001 | 29.57 |
| Senior general secondary education or pre-university secondary | 8.12 | 7.08 | P < 0.0001 | 7.75 |
| Higher vocational | 28.12 | 24.21 | P < 0.0001 | 26.72 |
| University | 7.44 | 6.22 | P < 0.0001 | 7.00 |
| Other | 1.62 | 1.49 | P = 0.1397 | 1.57 |
| Net income per month at last visit (1 = Less than €750, … , 11 = More than €5000), mean (sd) | 5.23 (1.76) | 4.98 (1.85) | P = 0.1340 | 5.23 (1.76) |
| Work situation at last visit (before COVID-19), % | ||||
| student | 0.48 | 0.64 | P < 0.0001 | 0.54 |
| paid work | 72.03 | 77.27 | P < 0.0001 | 73.91 |
| retired | 13.38 | 8.07 | P < 0.0001 | 11.48 |
| unfit for work | 2.92 | 3.06 | P = 0.7771 | 2.97 |
| unemployed/look- ing for work | 3.54 | 3.37 | P < 0.0001 | 3.48 |
| other | 7.64 | 7.60 | P = 0.0069 | 7.63 |