Data
1,325,314 items of data are available, covering 395,083 participants.
Some values have special meanings defined by Data-Coding
13.
Defined-instances run from 0 to 3, labelled using Instancing
2.
Array indices run from 0 to 33.
Units of measurement are years.
| Maximum | 2024.2 |
| Decile 9 | 2009.5 |
| Decile 8 | 2007.5 |
| Decile 7 | 2005.5 |
| Decile 6 | 2002.8 |
| Median | 1999.5 |
| Decile 4 | 1995.1 |
| Decile 3 | 1988.1 |
| Decile 2 | 1976.6 |
| Decile 1 | 1964.1 |
| Minimum | 1912.5 |
|
|
- Mean = 1993.42
- Std.dev = 17.8873
- 1 item below graph minimum of 1918.7
- 240 items have value -3 (Preferred not to answer)
- 50667 items have value -1 (Date uncertain or unknown)
|
4 Instances
Instance 0 : Initial assessment visit (2006-2010) at which participants were recruited and consent given
374,788 participants, 901,726 items
| Maximum | 2010.7 |
| Decile 9 | 2007.8 |
| Decile 8 | 2006.5 |
| Decile 7 | 2004.5 |
| Decile 6 | 2002.5 |
| Median | 1999.5 |
| Decile 4 | 1996.3 |
| Decile 3 | 1990.5 |
| Decile 2 | 1982.4 |
| Decile 1 | 1969.5 |
| Minimum | 1912.5 |
|
|
- Mean = 1994.08
- Std.dev = 15.2016
- 1 item below graph minimum of 1931.2
- 222 items have value -3 (Preferred not to answer)
- 32261 items have value -1 (Date uncertain or unknown)
|
Instance 1 : First repeat assessment visit (2012-13)
16,999 participants, 54,848 items
| Maximum | 2013.4 |
| Decile 9 | 2011.5 |
| Decile 8 | 2009.5 |
| Decile 7 | 2007.5 |
| Decile 6 | 2004.4 |
| Median | 2000.8 |
| Decile 4 | 1995.5 |
| Decile 3 | 1987.5 |
| Decile 2 | 1976.5 |
| Decile 1 | 1963.5 |
| Minimum | 1938.5 |
|
|
- Mean = 1993.78
- Std.dev = 18.1884
- 5 items have value -3 (Preferred not to answer)
- 818 items have value -1 (Date uncertain or unknown)
|
Instance 2 : Imaging visit (2014+)
64,253 participants, 286,301 items
| Maximum | 2024.2 |
| Decile 9 | 2018.5 |
| Decile 8 | 2015.3 |
| Decile 7 | 2011.5 |
| Decile 6 | 2005.5 |
| Median | 1998.5 |
| Decile 4 | 1986.6 |
| Decile 3 | 1973 |
| Decile 2 | 1964.6 |
| Decile 1 | 1957 |
| Minimum | 1938.8 |
|
|
- Mean = 1991.69
- Std.dev = 23.6893
- 13 items have value -3 (Preferred not to answer)
- 15465 items have value -1 (Date uncertain or unknown)
|
Instance 3 : First repeat imaging visit (2019+)
6,728 participants, 31,532 items
| Maximum | 2024.2 |
| Decile 9 | 2019.5 |
| Decile 8 | 2016.5 |
| Decile 7 | 2011.2 |
| Decile 6 | 2003.5 |
| Median | 1992.5 |
| Decile 4 | 1977.8 |
| Decile 3 | 1969.1 |
| Decile 2 | 1963.1 |
| Decile 1 | 1957 |
| Minimum | 1939.9 |
|
|
- Mean = 1989.71
- Std.dev = 24.4647
- 2123 items have value -1 (Date uncertain or unknown)
|
Notes
This is the interpolated time when the participant indicated the corresponding condition was first diagnosed by a doctor, measured in years.
- If the participant gave a calendar year, then the best-fit time is half-way through that year. For example if the year was given as 1970, then the value presented is 1970.5
- If the participant gave their age then the value presented is the fractional year corresponding to the mid-point of that age. For example, if the participant said they were 30 years old then the value is the date at which they were 30years+6months.
- Interpolated values before the date of birth were truncated forwards to that time.
- Interpolated values after the time of data acquisition were truncated back to that time.
Coding 13 defines 2 special values:
- -1 represents "Date uncertain or unknown"
- -3 represents "Preferred not to answer"
