| 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 |
[9] Adrenaline (epinephrine): Clifton W. Callaway, Michael W. Donnino, Ericka L. Fink, Romergryko G. Geocadin, Eyal Golan, Karl B. Kern, Marion Leary, William J. Meurer, Mary Ann Peberdy, Trevonne M. Thompson, Janice L. Zimmerman. 2015 American Heart Association Guidelines Update for Cardiopulmonary Resuscitation and Emergency Cardiovascular Care. Part 8: Post–Cardiac Arrest Care. Circulation. 2015;132:S465-S482. https://www.ncbi.nlm.nih.gov/pubmed/26472996