Lorazepam 1991, USA.

Study characteristics
Methods	Allocation: randomised. Blinding: double blind. Design: prospective. Duration: 48 hours ‐ intervention in an emergency situation; participants in both groups usually required only 1 parenteral injection for behavioural control during the study period (mean number of injections for lorazepam group = 1.13; mean number of injections for haloperidol group = 1.10). Setting: locked intensive care unit at Massachusetts Mental Health Center, Boston, US.
Participants	Diagnosis: schizophrenia (n = 16), bipolar (n = 11), schizoaffective disorder (n = 4), organic mental disorder (n = 6), other (n = 13). n = 60*. Age: mean 34 years. Gender: not stated. Ethnicity: not stated. Consent: not required. History: not stated. Inclusion: psychotic participants on a locked intensive care unit who required parenteral medication to control aggressive, assaultive or disruptive behaviour. Exclusion: known substance abuse documented by positive toxicology screen on admission.
Interventions	Benzodiazepines vs antipsychotics. 1. Lorazepam 2 mg IM, mean 1.13 injections (n = 30). 2. Haloperidol 5 mg IM, mean 1.10 injections (n = 30). Unclear when additional doses were given.
Outcomes	Global impression: no improvement*. Global impression: sedation. Adverse effects/events: EPS. Unable to use ‐ Global impression: CGI (no SD available). Behaviour: OAS (no SD available). Mental state: BPRS (no SD available).
Notes	*'Improvement' ‐ defined as a greater than mean decrease in OAS scores at 2 hours. "More bipolar participants received haloperidol by chance." *At the time of entering the study: ‐ n = 4 in the lorazepam group and n = 6 in the haloperidol group were receiving lithium carbonate. During the study period: ‐ n = 3 in the lorazepam group and n = 3 in the haloperidol group also received anticonvulsants. ‐ n = 3 in the lorazepam group and n = 3 in the haloperidol group also received beta‐blocking agents. ‐ n = 7 in the lorazepam group and n = 3 in the haloperidol group also received benzodiazepines. (Separate data analyses were conducted for participants receiving these additional psychotropic medications, but results did not differ.)
Risk of bias
Bias	Authors' judgement	Support for judgement
Random sequence generation (selection bias)	Unclear risk	Randomised ‐ no further description.
Allocation concealment (selection bias)	Unclear risk	Not stated.
Blinding (performance bias and detection bias) All outcomes	Low risk	Investigators were likely to have been blinded as the parenteral medication was prepared in advance by a member of the research staff who had no direct clinical responsibility for the participant. Rating scales: raters were blind to the treatment condition received by the participant. OAS ratings were obtained by staff nurses. BPRS ratings were obtained by "trained study psychiatrists." Adverse effects and sedation were assessed by clinicians who did not participate in evaluating therapeutic results.
Incomplete outcome data (attrition bias) All outcomes	Unclear risk	Follow‐up: sedation 88%; EPS 67%. ITT: not stated. Many participants were unavailable for all ratings ‐ "the number of patients available for rating after baseline declined in both treatment groups because some were discharged or transferred from the locked intensive care unit."
Selective reporting (reporting bias)	Unclear risk	Complete data not available ‐ SDs not available for most reported outcomes. BPRS and CGI data not reported for 48 hours post injection.
Other bias	Unclear risk	Funding: supported in part by Wyeth Laboratories. Unsure whether Wyeth Laboratories were involved in study design and reporting process.