Ford 1991.

Methods	RCT, parallel design
Participants	16 adult participants Elective procedures for atrial fibrillation or flutter. Three participants in each group were also cardiac surgery patients ASA II or III Hospital, Texas
Interventions	Etomidate (0.2% iv in 2‐mL aliquots every 15 seconds) Thiopental (2.5% iv in 2‐mL aliquots every 15 seconds) Aim: until patient no longer responded to verbal commands
Outcomes	Hypotension Unintended apneic episode Patient awareness/recall Success of cardioversion PONV Pain at site of injection Myoclonus Time to loss of consciousness Time to awakening Time to full recovery
Results	Etomidate vs Thiopental Hypotension (number of patients with decrease in MAP > 20%): 0/8 vs 0/8 Apnoea: 0/8 vs 0/8 Recall: 1/8 vs 1/8 PONV: 0/8 vs 0/8 Pain at injection site: 1/8 vs 0/8 Myoclonus: 3.8 vs 0/8 Successful cardioversion: 7/8 vs 7/8
Notes	Insufficient information supplied for baseline characteristics. No female participants in either group
Risk of bias
Bias	Authors' judgement	Support for judgement
Random sequence generation (selection bias)	Unclear risk	“Prospectively randomized into two study groups”. No further details
Allocation concealment (selection bias)	Unclear risk	No details
Blinding of participants and personnel (performance bias) Major adverse events	High risk	Clinician and anaesthesiologist not blinded
Blinding of participants and personnel (performance bias) Patient reported outcomes (recall/satisfaction)	High risk	Clinician and anaesthesiologist not blinded
Blinding of participants and personnel (performance bias) Success of cardioversion	High risk	Clinician and anaesthesiologist not blinded
Blinding of participants and personnel (performance bias) Minor adverse events	High risk	Clinician and anaesthesiologist not blinded
Blinding of participants and personnel (performance bias) Time to induction etc/need for resedation.	High risk	Clinician and anaesthesiologist not blinded
Blinding of outcome assessment (detection bias) Major adverse event	Low risk	Observer blinded
Blinding of outcome assessment (detection bias) Patient reported outcomes (recall/satisfaction)	Unclear risk	Participants blinded
Blinding of outcome assessment (detection bias) Success of cardioversion	Low risk	Observer blinded
Blinding of outcome assessment (detection bias) Minor adverse events	Low risk	Observer blinded
Blinding of outcome assessment (detection bias) Time to induction etc./need for resedation	Low risk	Observer blinded
Incomplete outcome data (attrition bias) All outcomes	Low risk	No apparent losses
Selective reporting (reporting bias)	Unclear risk	All outcomes from methods section reported  Prepublished protocol not sought
Other bias	Unclear risk	Baseline characteristics – insufficient information supplied. Also only males included in study External funding: no funding/conflicts of interest reported Anaesthetists: no details as to how many anaesthetists were involved in study