Data
555,381 items of data are available, covering 433,827 participants, encoded using Data-Coding 
100339.
Defined-instances run from 0 to 3, labelled using Instancing 
2.
 
4 Instances
Instance 0 : Initial assessment visit (2006-2010) at which participants were recruited and consent given
422,838 participants, 422,838 items
Instance 1 : First repeat assessment visit (2012-13)
17,548 participants, 17,548 items
Instance 2 : Imaging visit (2014+)
94,963 participants, 94,963 items
Instance 3 : First repeat imaging visit (2019+)
20,032 participants, 20,032 items
 
Notes
ACE touchscreen question "On what side of the head do you usually use a mobile phone?"
If the participant activated the Help button they were shown the message:
If you are unsure, please provide an estimate or select Do not know.
  | 
Field 1150 was collected from participants who indicated they have used a mobile phone at least once per week in the past or do not know whether they have used or not, as defined by their answers to Field 1110