Hosseini 2018.

Study characteristics
Methods	Controlled parallel‐group trial without randomisation
Participants	30 participants Inclusion criteria: aged 18–65 years; oriented to person, place, and date (GSC > 13); intubated for > 24 hours; literate at least at the primary school level; no previous history of ICU stay; no hearing/vision difficulties and mental illness. Exclusion criteria: none reported.
Interventions	Intervention A communication board partly derived from the Vidatak EZ Board (US 1999). Participant needs were illustrated on 1 side of the board using related images and written words. The other side of the board comprised 2 parts including a schematic picture of the body to determine pain locations and a whiteboard enabling the participant to write/draw. The research team taught clinical staff how to use the board. Control Usual care.
Outcomes	Ease of communication. Anxiety (anxiety subscale of the HADS).
Notes
Risk of bias
Bias	Authors' judgement	Support for judgement
Random sequence generation (selection bias)	High risk	Participants were divided into experimental and control groups by the research team.
Allocation concealment (selection bias)	High risk	As the researchers selected the allocation group, there was no allocation concealment.
Blinding of participants and personnel (performance bias) All outcomes	High risk	Participants and personnel were unable to be blinded due to the nature of the intervention.
Blinding of outcome assessment (detection bias) All outcomes	High risk	Questionnaires collected by the researcher.
Incomplete outcome data (attrition bias) All outcomes	Low risk	Outcome data reported on all participants.
Selective reporting (reporting bias)	Low risk	No evidence of selective reporting.
Other bias	Low risk	No evidence of other bias. Financial support and sponsorship: Urmia University of Medical Sciences, Urmia, Iran. Author conflict of interest: none stated.