Background Workflow interruptions, multitasking and workload demands are inherent to emergency departments (ED) work systems. Potential effects of ED providers’ work on care quality and patient safety have, however, been rarely addressed. We aimed to investigate the prevalence and associations of ED staff's workflow interruptions, multitasking and workload with patient care quality outcomes.

Methods We applied a mixed-methods design in a two-step procedure. First, we conducted a time-motion study to observe the rate of interruptions and multitasking activities. Second, during 20-day shifts we assessed ED staff's reports on workflow interruptions, multitasking activities and mental workload. Additionally, we assessed two care quality indicators with standardised questionnaires: first, ED patients’ evaluations of perceived care quality; second, patient intrahospital transfers evaluated by ward staff. The study was conducted in a medium-sized community ED (16 600 annual visits).

Results ED personnel's workflow was disrupted on average 5.63 times per hour. 30% of time was spent on multitasking activities. During 20 observations days, data were gathered from 76 ED professionals, 239 patients and 205 patient transfers. After aggregating daywise data and controlling for staffing levels, prospective associations revealed significant negative associations between ED personnel's mental workload and patients’ perceived quality of care. Conversely, workflow interruptions were positively associated with patient-related information on discharge and overall quality of transfer.

Conclusions Our investigation indicated that ED staff's capability to cope with demanding work conditions was associated with patient care quality. Our findings contribute to an improved understanding of the complex effects of interruptions and multitasking in the ED environment for creating safe and efficient ED work and care systems.