Barriers and Facilitators to HIV and Viral Hepatitis Testing in Primary Health Care Settings in the Kyrgyz Republic (BarTest): Protocol for a Mixed Methods Study - Ida Sperle; Nikolay Lunchenkov; Zuridin S Nurmatov; Aybek A Bekbolotov; Anastassiya Stepanovich-Falke; Michael Brandl; Olena Kysil; Stela Bivol; Viviane Bremer; Barbara Gunsenheimer-Bartmeyer; Sandra Dudareva (JMIR Research Protocols)