Table 1.

Characteristics of studies included in the meta-analysis

Reference	Total N	Included N	Setting	Control	Diagnosis	Patients with Concomitant Medications*
						N	%
Berman et al 2000 (10)	8	5	Outpatient	Saline	MDD	0	0
Valentine et al 2011 (25)	11	4	Outpatient	Saline	MDD	0	0
Sos et al 2013 (24)	27	9	Inpatient	Saline	MDD	9	100
Murrough et al 2013 (14)	73	35	Both**	Midazolam	MDD	0	0
Feder et al 2014 (22)	41	5	Both**	Midazolam	PTSD	0	0
Ballard et al 2014† (15)	87	59	Inpatient	Saline	MDD/BD	26	44
Hu et al 2015 (23)	27	26	Outpatient	Saline	MDD	26	100
Murrough et al 2015 (18)	24	24	Inpatient/Outpatient	Midazolam	Mixed††	19	79
Total	298	167				80	48

Abbreviations: MDD: major depressive disorder; BD: Bipolar Disorder; PTSD: posttraumatic stress disorder

^*Concomitant medications included antidepressants, antipsychotics, or mood stabilizers

^**Subjects were admitted as inpatients for ketamine infusion and then discharged as outpatients 24 hours following infusion

^†This was a review and secondary analysis of ketamine data from a research protocol evaluating the effects of ketamine on depressive symptoms (NCT00088699); publications from these results include Zarate CA et al., 2006 (11); Diazgranados et al., 2010 (13); and Zarate et al., 2012 (12).

^††The inclusion criterion for this investigation was suicidal ideation, not a specific DSM diagnosis. The most common diagnoses were MDD, BD, and PTSD.