Farahani 2012.

Study characteristics
Methods	Parallel‐group randomised controlled trial; 3‐arm study
Participants	60 participants Inclusion criteria: tracheally intubated and mechanically ventilated for ≥ 72 hours; not sedated; no hearing or visual impairment (glasses and hearing aids provided); able to speak Persian; no mental illness or cognitive problems. Exclusion criteria: people with probable or definitive diagnosis of brain injury (concussion, cerebral haemorrhage).
Interventions	Intervention 2 types of communication board. Board A comprised alphabet and words representing 2 categories of physical and mental needs. Board B comprised alphabet and pictures with various images of patient needs and potential demands. Control Usual care.
Outcomes	Satisfaction measured on a satisfaction questionnaire (no details provided) on a 1 (least) to 10 (most) satisfaction scale.
Notes	Article in Farsi and translated.
Risk of bias
Bias	Authors' judgement	Support for judgement
Random sequence generation (selection bias)	Unclear risk	No description. Further information sought but not obtained.
Allocation concealment (selection bias)	Unclear risk	No description. Further information sought but not obtained.
Blinding of participants and personnel (performance bias) All outcomes	High risk	Unable to blind due to nature of intervention.
Blinding of outcome assessment (detection bias) All outcomes	High risk	Outcomes were collected by the researcher who would have been aware of allocation.
Incomplete outcome data (attrition bias) All outcomes	Unclear risk	Only satisfaction scale reported.
Selective reporting (reporting bias)	Low risk	No obvious indication for concern. No trial registration.
Other bias	Low risk	No evidence of other bias. Funding source: none stated. Author conflict of interest: none stated.