Data
298,704 items of data are available, covering 236,512 participants.
Some values have special meanings defined by Data-Coding 
2536.
Defined-instances run from 0 to 3, labelled using Instancing 
2.
Units of measurement are correct-answers.
| Maximum | 13 |  
| Decile 9 | 8 |  
| Decile 8 | 7 |  
| Decile 7 | 7 |  
| Decile 6 | 6 |  
| Median | 6 |  
| Decile 4 | 5 |  
| Decile 3 | 4 |  
| Decile 2 | 4 |  
| Decile 1 | 3 |  
| Minimum | 0 |  
 
 | 
 
 | 
- There are 14 distinct values.
 
- Mean = 5.60236
 
- Std.dev = 2.01301
 
- 1 items have value -1 (Not calculable due to unclean data)
 
  | 
 
4 Instances
Instance 0 : Initial assessment visit (2006-2010) at which participants were recruited and consent given
165,284 participants, 165,284 items
| Maximum | 13 |  
| Decile 9 | 8 |  
| Decile 8 | 7 |  
| Decile 7 | 6 |  
| Decile 6 | 6 |  
| Median | 5 |  
| Decile 4 | 5 |  
| Decile 3 | 4 |  
| Decile 2 | 4 |  
| Decile 1 | 3 |  
| Minimum | 0 |  
 
 | 
 
 | 
- There are 14 distinct values.
 
- Mean = 5.39718
 
- Std.dev = 2.0283
 
  | 
Instance 1 : First repeat assessment visit (2012-13)
20,091 participants, 20,091 items
| Maximum | 13 |  
| Decile 9 | 9 |  
| Decile 8 | 7 |  
| Decile 7 | 7 |  
| Decile 6 | 6 |  
| Median | 6 |  
| Decile 4 | 5 |  
| Decile 3 | 5 |  
| Decile 2 | 4 |  
| Decile 1 | 4 |  
| Minimum | 0 |  
 
 | 
 
 | 
- There are 14 distinct values.
 
- Mean = 5.94186
 
- Std.dev = 1.9897
 
  | 
Instance 2 : Imaging visit (2014+)
93,584 participants, 93,584 items
| Maximum | 13 |  
| Decile 9 | 8 |  
| Decile 8 | 7 |  
| Decile 7 | 7 |  
| Decile 6 | 6 |  
| Median | 6 |  
| Decile 4 | 5 |  
| Decile 3 | 5 |  
| Decile 2 | 4 |  
| Decile 1 | 3 |  
| Minimum | 0 |  
 
 | 
 
 | 
- There are 14 distinct values.
 
- Mean = 5.82228
 
- Std.dev = 1.96475
 
- 1 items have value -1 (Not calculable due to unclean data)
 
  | 
Instance 3 : First repeat imaging visit (2019+)
19,745 participants, 19,745 items
| Maximum | 13 |  
| Decile 9 | 8 |  
| Decile 8 | 7 |  
| Decile 7 | 7 |  
| Decile 6 | 6 |  
| Median | 6 |  
| Decile 4 | 5 |  
| Decile 3 | 5 |  
| Decile 2 | 4 |  
| Decile 1 | 4 |  
| Minimum | 0 |  
 
 | 
 
 | 
- There are 14 distinct values.
 
- Mean = 5.93219
 
- Std.dev = 1.93184
 
- 12 items above graph maximum of 12
 
  | 
 
Notes
This is a simple unweighted sum of the number of correct answers given to the 13 fluid intelligence questions. Participants who did not answer all of the questions within the allotted 2 minute limit are scored as zero for each of the unattempted questions.
Coding 2536 defines 1 special value:
- -1 represents "Not calculable due to unclean data"