TABLE 1.
Sociodemographic characteristics of the samples.
| Cohort | 0 | 1 | 2 | 3 | 4 | 5 | 6 | 7 | |
|---|---|---|---|---|---|---|---|---|---|
| Pre‐pandemic | Apr 2020 | Nov 2020 | Apr 2021 | Nov 2021 | Apr 2022 | Nov 2022 | Apr 2023 | ||
| NTR | N total | 13,950 | 1791 | 536 | 714 | 855 | 883 | 818 | – |
| N after random selection a | 13,345 | 1296 | 220 | 297 | 372 | 376 | 329 | – | |
| Male | 49.2% | 48.7% | 50.9% | 54.2% | 46.5% | 50.5% | 53.2% | – | |
| M age (SD) | 11.6 (1.3) | 10.8 (1.8) | 10.5 (2.0) | 10.2 (2.1) | 10.9 (2.2) | 11.2 (1.9) | 11.3 (2.2) | – | |
| Country of birth parents (both Dutch) b | 93.0% | 92.3% | 92.6% | 88.8% | 94.5% | 91.2% | 92.2% | – | |
| Educational level parents low c | 19.4% | 2.9% | 1.9% | 1.9% | 2.4% | 1.9% | 0.8% | – | |
| Educational level parents intermediate c | 39.0% | 28.8% | 30.9% | 25.7% | 24.0% | 23.0% | 20.8% | – | |
| Educational level parents high c | 41.6% | 68.3% | 67.3% | 72.3% | 73.6% | 75.1% | 78.4% | – | |
| KLIK | N total | 2401 | 856 | 939 | 909 | 828 | 893 | 945 | 1056 |
| N after random selection a | 2401 | 496 | 591 | 445 | 402 | 505 | 538 | 663 | |
| Male | 50.3% | 46.2% | 52.0% | 53.5% | 52.2% | 49.7% | 48.5% | 51.89% | |
| M age (SD) | 13.1 (3.1) | 13.5 (2.9) | 13.8 (3.2) | 13.6 (3.3) | 13.7 (3.1) | 13.5 (3.1) | 13.6 (3.3) | 13.5 (3.1) | |
| Country of birth parents (both Dutch) | 93.0% d | 86.3% | 88.4% | 87.9% | 86.3% | 89.5% | 88.5% | 89.1% | |
| Educational level parents low | 12.8% d | 9.1% | 9.8% | 9.7% | 9.5% | 6.7% | 7.1% | 8.7% | |
| Educational level parents intermediate | 48.2% | 53.2% | 51.4% | 45.8% | 49.5% | 48.6% | 49.8% | 47.2% | |
| Educational level parents high | 38.9% | 37.7% | 38.7% | 44.5% | 41.0% | 44.6% | 43.1% | 44.0% | |
| DREAMS | N total | – | 500 | 892 | 661 | 632 | 450 | 420 | 367 |
| N after random selection a | – | 483 | 833 | 607 | 562 | 398 | 370 | 320 | |
| Male | – | 55.3% | 53.4% | 59.1% | 55.2% | 47.7% | 47.6% | 52.5% | |
| M age (SD) | – | 13.3 (3.1) | 13.6 (2.9) | 13.0 (2.9) | 13.2 (2.9) | 13.4 (2.9) | 13.4 (2.9) | 13.5 (2.7) | |
| Country of birth parents (both Dutch) | – | 84.4% | 88.8% | 87.1% | 86.0% | 85.2% | 85.4% | 88.4% | |
| Educational level parents low | – | 4.5% | 5.4% | 5.8% | 6.3% | 5.7% | 6.8% | 3.8% | |
| Educational level parents intermediate | – | 40.3% | 44.4% | 41.8% | 43.4% | 38.5% | 37.0% | 38.1% | |
| Educational level parents high | – | 55.2% | 50.2% | 52.5% | 50.4% | 55.7% | 56.3% | 58.1% |
Note: Statistics represent the samples after random selection of a single measurement moment for each participant.
Abbreviations: M, mean; N, number of participants; SD, standard deviation.
a
Number of participants after random selection of one measurement for each individual participant.
b
4%–13% of data are missing per measurement. Shown percentages are valid percentages (excluding missing cases).
c
4%–25% of data are missing per measurement. Shown percentages are valid percentages (excluding missing cases).
d
Sample size is smaller (N = 1082) as data were not collected in norm studies for PROMIS anxiety and depressive symptoms.