1. School of Public Health, Moi University, Eldoret, Kenya
2. Centre for Respiratory Disease Research, Kenya Medical Research Institute, Nairobi, Kenya
3. Department of Public Health, Policy and Systems, University of Liverpool, Liverpool, UK
4. Department of Health Services Research and Policy, London School of Hygiene & Tropical Medicine, London, UK
5. Kintampo Health Research Centre, Research and Development Division, Ghana Health Service, Kintampo North Municipality, Bono East Region, Ghana