Acquisition of patients' EHR information under ED congestion - an empirical investigation.

We examine the information acquisition process regarding a patient's status under emergency department (ED) congestion conditions. We focus on two key information channels: 1) Electronic Health Record (EHR) that provide the patient's medical history and 2) Medical tests conducted in real-time. Whereas the EHR provides the physician with easily accessible information with little delay, real-time medical tests can provide more current information, but are time-consuming. We examine physicians' decisions in cases of ED congestion, using a dataset that includes more than 1.4 million visits. When congestion is low, the information channels are complementary - acquiring information from the EHR is positively correlated with information acquisition from the medical tests channel, representing an incentive for the physician to acquire all possible information before providing diagnosis. However, as the congestion increases, there is less reliance on medical tests; this effect is amplified when EHR information is used. To avoid excessive congestion, physicians apparently refrain from sending patients for medical tests, and compensate for loss of information using EHR information. The impact of high system workload on the quality of medical service is an essential concern for managers; we show the indirect benefit of investment in EHRs through reduced blood-tests without increasing revisit rates.