Year and cohort (C) | Wave | Method | Age | Eligible start of Wave | With-drawn | Wrong address* | Received quest. | Got data | (%) return rate of those still in study | (%) return rate of original eligible sample |
---|---|---|---|---|---|---|---|---|---|---|
1996 C1 | 1 | Classroom | 13-14 | 4234 | 171 | N/A1 | 4063 | 3812 | 93.8 | 90.0 |
1997 C2 | 1 | Classroom | 13-14 | 4196 | 165 | N/A1 | 4031 | 3804 | 94.4 | 90.7 |
1998 C1 | 2 | Classroom + postal2 | 15-16 | 4197 | 174* | 147* | 3876 | 2991 | 77.2 | 71.3 |
1999 C2 | 2 | Classroom + postal2 | 15-16 | 4187 | 137* | 176* | 3874 | 2863 | 73.9 | 68.4 |
2000 C1 | 3 | Postal | 17-18 | 3876 | 127* | 313* | 3436 | 1116 | 32.5 | 26.4 |
2001 C2 | 3 | Postal | 17-18 | 3874 | 32* | 282* | 3560 | 1739 | 48.8 | 41.4 |
2002 C1 | 4 | Mix3 | 19-20 | 3436 | 604* | 32* | 2800 | 1047 | 37.4 | 30.5 |
2003 C2 | 4 | Postal | 19-20 | 3560 | 598* | 10* | 2952 | 1439 | 48.7 | 40.4 |