| 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] Antidepressants: ACOG Committee on Practice Bulletins--Obstetrics. ACOG Practice Bulletin: Clinical management guidelines for obstetrician-gynecologists number 92, April 2008 (replaces practice bulletin number 87, November 2007). Use of psychiatric medications during pregnancy and lactation. Obstet Gynecol. 2008 Apr;111(4):1001–20. https://www.ncbi.nlm.nih.gov/pubmed/18378767
Antidepressants: National Institute of Clinical Excellence: National Clinical Guideline Number 192: Antenatal and postnatal mental health – clinical management and service guidance, April 2018. https://www.nice.org.uk/guidance/cg192/evidence/full-guideline-pdf-4840896925