2. Suggested design for a trial.

Methods	Allocation: randomised, clearly described, concealed. Blindness: double, described and tested. Duration: 2 weeks.
Participants	Diagnosis: thought to be psychoses. N = 300.* Age: any. Sex: both. History: acutely ill, aggressive and/or agitated.
Interventions	1. Aripiprazole IM: dose flexible within recommended limits. N = 150. 2. Haloperidol IM: dose flexible within recommended limits. N = 150.
Outcomes	All outcomes are grouped by time: by 30 minutes, up to two hours, up to four hours, up to 24 hours, and over 24 hours. Tranquillisation or asleep ‐ tranquil; asleep. Repeated need for tranquillisation ‐ needing additional injections. Specific behaviours ‐ self‐harm, including suicide, injury to others. Global outcomes ‐ patient satisfaction; use of restraint or seclusion. Service outcomes ‐ length of hospitalisation; readmission rate. Mental state ‐ effect of medication on mental state. Adverse effects ‐ medication significant side effects. Leaving the study early ‐ detailed reasons provided. Quality of life outcomes. Economic outcomes.
Notes	* Powered to be able to identify a difference of ˜20% between groups for primary outcome with adequate degree of certainty

IM: intramuscular