Carspecken 2018.

Study characteristics
Methods	Double‐blinded randomised clinical trial
Participants	Veterans scheduled for an index course of ECT for treatment of a major depressive episode associated with treatment resistant major depressive disorder Diagnosis: DSM‐V major depressive disorder N: 52 Age:kKetamine group M = 50 (SD = 12); methohexital M = 47 (SD 12) Sex: ketamine 26% female; Methohexital 11% female Baseline depression severity: ketamine group PHQ‐9 M = 21.1 (SD = 3.9); Methohexital group PHQ‐9 M = 21.5 (SD = 3.6)
Interventions	Intravenous racemic ketamine (1‐2 mg/kg) or methohexital (1‐2 mg/kg), in addition to ketorolac 30 mg for induction of general anesthesia. Participants in the ketamine arm received 1 mg to 2 mg of IV midazolam to mitigate post‐procedural psychedelic effects. Concomitant treatment: yes. Quote: "Outpatient benzodiazepines were discontinued 48 hours before ECT, whereas all other psychiatric medications were continued during the study."
Outcomes	HAM‐D PHQ‐9 MOCA
Notes
Risk of bias
Bias	Authors' judgement	Support for judgement
Random sequence generation (selection bias)	Low risk	Quote: “"Patient randomization was performed using permuted block randomization to ensure number of subjects assigned to each treatment arm was balanced"
Allocation concealment (selection bias)	Low risk	Quote: “"Patient randomization was performed using permuted block randomization to ensure number of subjects assigned to each treatment arm was balanced"
Blinding of participants and personnel (performance bias) All outcomes	Unclear risk	Quote: “"Subjects and depression score raters were blinded to study drug intervention. Because of feasibility issues, anesthesiologists and psychiatrists were not blinded during ECT sessions." Effectiveness of blinding not assessed.
Blinding of outcome assessment (detection bias) All outcomes	Unclear risk	Effectiveness of blinding not assessed. Unclear if cognitive measured were blinded as they were completed by psychiatrists who were not blinded.
Incomplete outcome data (attrition bias) All outcomes	Low risk	Study CONSORT flow chart included.
Selective reporting (reporting bias)	Low risk	Study protocol available, outcomes reported as expected.
Other bias	Low risk	None identified.