| 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 |
[24] Betamethasone, IM: Roberts D, Dalziel S. Antenatal corticosteroids for accelerating fetal lung maturation for women at risk of preterm birth. Cochrane Database Syst Rev. 2006 Jul 19;(3):CD004454.http://www.ncbi.nlm.nih.gov/pubmed/16856047
Betamethasone, IM: Royal College of Obstetricians and Gynaecologists. Green-top Guideline No.7: Antenatal corticosteroids to reduce neonatal morbidity and mortality. October 2010. Available at: https://www.rcog.org.uk/globalassets/documents/guidelines/gtg_7.pdf