1 Cochrane South Africa, South African Medical Research Council, Cape Town 7500, South Africa; Division of Epidemiology and Biostatistics, Department of Global Health, Faculty of Medicine and Health Sciences, Stellenbosch University, Cape Town, South Africa. Electronic address: abdu.adamu@gmail.com.
2 Cochrane South Africa, South African Medical Research Council, Cape Town 7500, South Africa.
3 Department of Community Medicine, Bayero University-Aminu Kano Teaching Hospital, Kano, Nigeria.
4 Department of Obstetrics and Gynecology, Bayero University-Aminu Kano Teaching Hospital, Kano, Nigeria.
5 Cochrane South Africa, South African Medical Research Council, Cape Town 7500, South Africa; Division of Epidemiology and Biostatistics, Department of Global Health, Faculty of Medicine and Health Sciences, Stellenbosch University, Cape Town, South Africa; Communicable and Non-Communicable Diseases Cluster, World Health Organization Regional Office for Africa, Brazzaville, Congo.