Cohort participation and retention
Timeline of surveys since 1996
| Cohort | 1989-95 | 1973-78 | 1946-51 | 1921-26 |
|---|---|---|---|---|
| Survey 1 | 2013 (age 18-23) | 1996 (age 18-23) | 1996 (age 45-50) | 1996 (age 70-75) |
| N=17 011 | N=14 247 | N=13 714 | N=12 432 | |
| Survey 2 | 2014 (age 19-24) | 2000 (age 22-27) | 1998 (age 47-52) | 1999 (age 73-78) |
| N=11 344 | N=9688 | N=12 338 | N=10 434 | |
| Survey 3 | 2015 (age 20-25) | 2003 (age 25-30) | 2001 (age 50-55) | 2002 (age 76-81) |
| N=8961 | N=9081 | N=11 226 | N=8646 | |
| Survey 4 | 2016 (age 21-26) | 2006 (age 28-33) | 2004 (age 53-58) | 2005 (age 79-84) |
| N=9007 | N=9145 | N=10 905 | N=7158 | |
| Survey 5 | 2017 (age 22-27) | 2009 (age 31-36) | 2007 (age 56-61) | 2008 (age 82-87) |
| N=8495 | N=8199 | N=10 638 | N=5560 | |
| Survey 6 | 2019 (age 24-29) | 2012 (age 34-39) | 2010 (age 59-64) | 2011 (age 90-95) |
| In progress | N=8009 | N=10 011 | N=4055 | |
| Survey 7 | 2015 (age 37-42) | 2013 (age 62-67) | Surveyed at six monthly intervals from November 2011 (see next table) |
|
| N=7186 | N=9151 | |||
| Survey 8 | 2018 (age 40-45) | 2016 (age 65-70) | ||
| N=7121 | N=8622 | |||
| Survey 9 | 2019 (age 68-73) | |||
| In progress |
1921-26 Cohort, six-monthly follow up (6MF) showing year and age
| Survey | Total number Aged | 2011 85-90 | 2012 86-91 | 2013 87-92 | 2014 88-93 | 2015 89-94 | 2016 90-95 | 2017 91-96 | 2018 92-98 | 2019 93-99 |
|---|---|---|---|---|---|---|---|---|---|---|
| 6MF1 | N=3855 | 2829 | 945 | 59 | 13 | 2 | 4 | 1 | 2 | 0 |
| 6MF2 | N=3393 | 3069 | 248 | 45 | 14 | 8 | 1 | 5 | 3 | |
| 6MF3 | N=2992 | 1651 | 1178 | 96 | 33 | 16 | 8 | 6 | 4 | |
| 6MF4 | M=2614 | 2216 | 292 | 57 | 27 | 8 | 12 | 2 | ||
| 6MF5 | N=2297 | 921 | 1169 | 133 | 41 | 16 | 12 | 5 | ||
| 6MF6 | N=2013 | 1591 | 299 | 64 | 33 | 18 | 8 | |||
| 6MF7 | N=1760 | 595 | 985 | 110 | 35 | 29 | 6 | |||
| 6MF8 | N=1529 | 1129 | 311 | 52 | 28 | 9 | ||||
| 6MF9 | N=1353 | 439 | 737 | 133 | 33 | 11 | ||||
| 6MF10 | N=1185 | 823 | 285 | 56 | 21 | |||||
| 6MF11 | N=1027 | 260 | 612 | 124 | 31 | |||||
| 6MF12 | N=865 | 569 | 252 | 44 | ||||||
| 6MF13 | N=712 | 160 | 479 | 73 | ||||||
| 6MF14 | N=573 | 415 | 158 | |||||||
| 6MF15 | N=381 | 116 | 265 | |||||||
| 6MF16 | N=153 | 153 |