[1] Monklands Hosp, Dept Med, Airdrie ML6 0JS, Lanark, Scotland
[2] Monklands Hosp, Dept Biochem, Airdrie ML6 0JS, Lanark, Scotland
[3] Greater Glasgow NHS Board, Dept Publ Hlth, Glasgow, Lanark, Scotland
[4] Common Serv Agcy, Record Linkage Dept, Informat & Stat Div, Edinburgh, Midlothian, Scotland