1. Centre for Primary Care Research, University of Zambia School of Medicine, PO Box 50110, Lusaka, Zambia
2. Mufulira School of Nursing & Midwifery, Mufulira, Zambia
3. Kalulushi College of Nursing, Kalulushi, Zambia
4. Faculty of Nursing, Rusangu University, Monze, Zambia
5. Centre for Primary Care Research, PO Box 50110, Lusaka, Zambia
6. Imperial Clinical Trials Unit, Imperial College London, Stadium House, 68 Wood Lane, London W12 7RH, UK