1. No affiliation; 12-22 Linenhall Street Belfast Northern Ireland UK BT2 8BS
2. Queen's University Belfast; School of Pharmacy; 97 Lisburn Road Belfast Northern Ireland UK BT9 7BL
3. University of Auckland; Department of General Practice and Primary Health Care; Private Bag 92019 Auckland New Zealand
4. Queen's University Belfast; Centre for Public Health; School of Medicine Dentistry and Biomedical Sciences, Belfast Northern Ireland UK BT12 6BJ