| 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] Polyvalent snake antivenom (indications): Wood D, Sartorius B, Hift R. Snakebite in NE South Africa: clinical characteristics and risks for severity. S Afr Fam Prac 2016; 58(2):62-67. https://www.tandfonline.com/doi/full/10.1080/20786190.2015.1120934
Polyvalent snake antivenom (indications): Wood, Sartorius, Hift. Classifying snakebite in South Africa: validating a scoring system. S Afr Med J 2017;107(1):46-51. https://www.ncbi.nlm.nih.gov/pubmed/28112091