1. Department of Public Health, The University of Texas at Tyler, Tyler, TX 75799, USA
2. Department of Public Health, South Eastern Kenya University (SEKU), Kitui 90200, Kenya
3. Department of Public Health, Masinde Muliro University of Science and Technology, Kakamega 50100, Kenya
4. Department of Public Health, Kisii University, Kisii 40200, Kenya
5. School of Medicine at the Health Science Center, The University of Texas at Tyler, Tyler, TX 75799, USA