| 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 |
[5] The health and human services panel on treatment of HIV-infected pregnant women and prevention of perinatal transmission - A working group of the office of AIDS research advisory Council.Guidelines for the use of Antiretroviral Agents in Pediatric HIV Infection.
http://aidsinfo.nih.gov/contentfiles/lvguidelines/pediatricguidelines.pdf.