| Level I | Good quality evidence |
Systematic review of RCTs with consistent findings High quality individual RCT |
| Level II |
Limited quality patient orientated evidence |
Systematic review of lower quality studies or studies with inconsistent findings Low quality clinical trial Cohort studies Case-control studies |
| Level III | Other |
Consensus guidelines, extrapolations from bench research, usual practice, opinion, disease-oriented evidence (intermediate or physiologic outcomes only), or case series |
[12] Tenofovir, oral (Renal function in HIV infected patients on nephrotoxic medicines): Kenyon C, Wearne N, Burton R, Meintjes G. The Risks of Concurrent Treatment with Tenofovir and Aminoglycosides in Patients with HIV-Associated Tuberculosis. South Afr J HIV Med 2011;12(1):43–45. http://www.ncbi.nlm.nih.gov/pubmed/21695064