Published on in Vol 16, No 2 (2014): February
1 General Practice & Primary Care, Institute of Health & Wellbeing, College of Medical, Veterinary & Life Sciences, University of Glasgow, Glasgow, United Kingdom
2 Institute of Health & Wellbeing, College of Social Sciences, University of Glasgow, Glasgow, United Kingdom
3 Respiratory Medicine, Institute of Infection, Immunity & Inflammation, University of Glasgow, Glasgow, United Kingdom
4 Forth Valley Royal Hospital, NHS Forth Valley, United Kingdom
5 Robertson Centre for Biostatistics, Institute of Health & Wellbeing, College of Medical, Veterinary & Life Sciences, University of Glasgow, Glasgow, United Kingdom
6 School of Medicine, University of Glasgow, Glasgow, United Kingdom