| 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 |
[17] Morphine syrup (Children: palliative dyspnoea): Johnston DL, Hentz TA, Friedman DL. Pediatric palliative care. J Pediatr Pharmacol Ther. 2005 Oct;10(4):200-14. https://www.ncbi.nlm.nih.gov/pubmed/23118638
Morphine syrup (Children: palliative dyspnoea): National Department of Health: Affordable Medicines, EDP- PHC. Medicine Review: Morphine, oral for palliative dyspnoea in adults and children, September 2017. http://www.health.gov.za/