1. Department of Nursing and Midwifery; University of Limerick; Limerick Ireland
2. School of Nursing and Midwifery; National University of Ireland, Galway; Galway Ireland
3. Galway Ireland
4. Ageing Research Centre, School of Allied Health; University of Limerick; Limerick Ireland
5. Norwegian Institute of Public Health; Oslo Norway
6. Nuffield Department of Population Health; University of Oxford; Oxford UK
7. School of Health and Related Research; University of Sheffield, ScHARR; Sheffield UK
8. Department of Clinical Sciences; University of Bergen; Bergen Norway
9. Centre for Tropical Medicine and Global Health; University of Oxford; Oxford UK