Objectives Research in outpatient setting suggests that the presence of companions during a medical encounter can improve clinician–patient communication. It is not known if the presence of companions has a similar effect in the acutely stressful context of the ED. This study tested whether the presence of companions in the ED relate to stronger clinician–patient communication. We further explored effect modification by demographic factors (race/ethnicity, education and language) thought to compromise communication.

Methods Participants were drawn from an observational cohort study of patients with suspected acute coronary syndrome (n=876) recruited from an urban academic medical centre between 2013 and 2016. Patient interviews occurred both in the ED and post-ED discharge; communication was assessed using the Interpersonal Processes of Care Survey with possible range of scores of 14–70. Companions were categorised as close others (ie, partner/spouse or child), non-close others (eg, neighbour) or no one.

Results Perceptions of clinician–patient communication were high (mean=57.1, SD=10.6;). There was no association between companions (close/non-close/no one) and clinician–patient communication, p=0.262. Demographic factors were unrelated to communication. There was a significant interaction between education and companions. Having a close other in the ED was associated with stronger clinician–patient communication only for patients with high school education or less, p=0.027.

Conclusions Neither the presence of companions nor demographic factors were related to clinician–patient communication. The interaction effect suggesting that patients completing high school or less have the most to gain from the presence of close others warrants further exploration.