[1] NHS Natl Serv Scotland, Informat Serv Div, Edinburgh EH12 9EB, Midlothian, Scotland
[2] Univ Edinburgh, Dept Publ Hlth Sci, Edinburgh EH8 9AG, Midlothian, Scotland
[3] Univ Aberdeen, Aberdeen AB25 2ZP, Scotland
[4] Univ Dundee, Biomed Res Inst, Diabet Res Grp, Dundee DD1 9SY, Scotland