Study characteristics	Eligibility criteria	Y/N or unclear	Details and location
Type of study	Randomized controlled trial
	Controlled clinical trial (quasi‐randomized trial and cluster‐randomized trial)
Participants	Adults > 16 years undergoing electrical cardioversion in the emergency or elective setting
Types of intervention and comparison We will include studies comparing 2 different anaesthetic agents or different doses of the same agent Groups may include the additional use of an analgesic (e.g. fentanyl, alfentanil) by its use alone or by dose	Comparison of 1 of:
	intravenous anaesthetic agents (e.g. etomidate, propofol, thiopentone, methohexital);
	inhaled anaesthetic agents (e.g. isoflurane, sevoflurane);
	sedative agents (e.g. midazolam, diazepam) via any route (intramuscular, subcutaneous, intravenous, rectal); or
	analgesic (e.g. fentanyl, alfentanil).
	With one of:
	intravenous anaesthetic agents (e.g. etomidate, propofol, thiopentone, methohexital);
	inhaled anaesthetic agents (e.g. isoflurane, sevoflurane); or
	sedative agents (e.g. midazolam, diazepam) via any route (intramuscular, subcutaneous, intravenous, rectal).