1. University of Calabar; Department of Public Health, College of Medical Sciences; Calabar Cross River State Nigeria PMB 1115
2. University of Arizona, Mel & Enid Zuckerman College of Public Health; Division of Health Promotion Sciences; 1295 N. Martin Avenue A256 Campus POB: 245163 Tucson Arizona USA AZ 85724
3. Institute of Tropical Diseases Research and Prevention; Nigerian Branch of the South African Cochrane Centre; University of Calabar Teaching Hospital, Moore Road Calabar Cross River State Nigeria 540261
4. University of Calabar Teaching Hospital; Department of Paediatrics; PMB 1115 Calabar Cross River State Nigeria
5. St George's, University of London; Population Health Sciences Institute; Cranmer Terrace London UK SW17 0RE