How Are Patient Order and Shift Timing Associated with Imaging Choices in the Emergency Department? Evidence From Niagara Health Administrative Data.

STUDY OBJECTIVE: We assessed whether the timing and order of patients over emergency shifts are associated with receiving diagnostic imaging in the emergency department and characterized whether changes in imaging are associated with changes in patients returning to the ED. METHODS: In this retrospective study, we used multivariate and instrumental variable regressions to examine how the timing and order of patients are associated with the use of diagnostic imaging. Outcomes include whether a patient receives a radiograph, a computed tomography (CT) scan, an ultrasound, and 7-day bouncebacks to the ED. The variables of interest are time and order during a physician's shift in which a patient is seen. RESULTS: A total of 841,683 ED visits were examined from an administrative database of all ED visits to Niagara Health. Relative to the first patient, the probability of receiving a radiograph, CT, and ultrasound decreases by 6.4%, 9.1%, and 3.8% if a patient is the 15th patient seen during a shift. Relative to the first minute, the probability of receiving a radiograph, CT, or ultrasound increases by 1.9%, 2.7%, and 1.1% if a patient is seen in the 180th minute. Seven-day bounceback rates are not consistently associated with patient order or timing in a shift and imaging orders. CONCLUSION: Imaging in the ED is associated with shift length and especially patient order, suggesting that physicians make different imaging decisions over the course of their shifts. Additional imaging does not translate into reductions in subsequent bouncebacks to the hospital.

Exploring the impact of diagnostic imaging decision support embedded in an electronic referral solution on the appropriate ordering of magnetic resonance imaging for patients with knee pain: a retrospective chart review.

RATIONAL AND OBJECTIVE: Requests for magnetic resonance imaging (MRI) exams have notably increased in Canada. However, many of these exams may not always be indicated. The Joint Department of Medical Imaging and the eReferral Program have worked collaboratively to embed an integrated clinical decision support (DS) tool within the eReferral process for diagnostic imaging requests. This retrospective chart review aimed to assess the necessity of MRI exams for knee pain patients at the point of referral in relation to the referral method (no DS tools within fax- vs. DS tools within eReferral). METHODS: Seven hundred and seventeen medical charts of routine MRI referral requests to an Ontario Hospital for patients with knee complaints were reviewed during the study period. The necessity of the MRI exams was evaluated using the supporting algorithm and knee pathway appropriateness guidelines. MRI exams were considered necessary if requested for symptoms or signs that align with best-practice standards, complemented with sound clinical assessment or history of a radiography scan before ordering an MRI. RESULTS: In general, MRI requests made through eReferral were 13.289 times more likely to be necessary orders than those made through fax. The likelihood of referring patients for a necessary MRI exam was higher for eReferral than fax for the year 2018/2019 (53.0% vs. 26.8%, P < 0.001) and for the year 2019/2020 (58.5% vs. 16.3%, P < 0.001). In addition, the rate of ordering X-ray as the proper initial imaging scan for patients presenting with knee pain has steadily increased by 10% over the year for users of the eReferral platform compared to a decrease of 7% for those using fax. CONCLUSION: Our findings highlight the positive impact of integrating DS tools at the point of referral in supporting the ordering of necessary MRI scans, suggesting that service re-design and implementation of automated assistive technology services would impact patient care.