| 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 |
[26] Selective serotonin reuptake inhibitors, oral (duration of therapy – depression): Bauer M, Severus E, Köhler S, Whybrow PC, Angst J, Möller HJ; Wfsbp Task Force on Treatment Guidelines for Unipolar Depressive Disorders. World Federation of Societies of Biological Psychiatry (WFSBP) guidelines for biological treatment of unipolar depressive disorders. part 2: maintenance treatment of major depressive disorder-update 2015. World J Biol Psychiatry. 2015 Feb;16(2):76-95. https://www.ncbi.nlm.nih.gov/pubmed/25677972
Selective serotonin reuptake inhibitors, oral (duration of therapy – depression): World Health Organisation. mhGAP intervention guide for mental, neurological and substance use disorders in non-specialized health settings: mental health Gap Action Programme (mhGAP), version 2.0. Geneva, 2016
http://www.who.int/mental_health/mhgap/mhGAP_intervention_guide_02/en/
Selective serotonin reuptake inhibitors, oral (duration of therapy – depression): Geddes JR, Carney SM, Davies C, Furukawa TA, Kupfer DJ, Frank E, Goodwin GM. Relapse prevention with antidepressant drug treatment in depressive disorders: a systematic review. Lancet. 2003 Feb 22;361(9358):653-61. https://www.ncbi.nlm.nih.gov/pubmed/12606176