Machine Learning Methods for Predicting Patient-Level Emergency Department Workload



      Work Relative Value Units (wRVUs) are a component of many compensation models, and a proxy for the effort required to care for a patient. Accurate prediction of wRVUs generated per patient at triage could facilitate real-time load balancing between physicians and provide many practical operational and clinical benefits.


      We examined whether deep-learning approaches could predict the wRVUs generated by a patient's visit using data commonly available at triage.


      Adult patients presenting to an urban, academic emergency department from July 1, 2016–March 1, 2020 were included. Deidentified triage information included structured data (age, sex, vital signs, Emergency Severity Index score, language, race, standardized chief complaint) and unstructured data (free-text chief complaint) with wRVUs as outcome. Five models were examined: average wRVUs per chief complaint, linear regression, neural network and gradient-boosted tree on structured data, and neural network on unstructured textual data. Models were evaluated using mean absolute error.


      We analyzed 204,064 visits between July 1, 2016 and March 1, 2020. The median wRVUs were 3.80 (interquartile range 2.56–4.21), with significant effects of age, gender, and race. Models demonstrated lower error as complexity increased. Predictions using averages from chief complaints alone demonstrated a mean error of 2.17 predicted wRVUs per visit (95% confidence interval [CI] 2.07–2.27), the linear regression model: 1.00 wRVUs (95% CI 0.97–1.04), gradient-boosted tree: 0.85 wRVUs (95% CI 0.84–0.86), neural network with structured data: 0.86 wRVUs (95% CI 0.85–0.87), and neural network with unstructured data: 0.78 wRVUs (95% CI 0.76–0.80).


      Chief complaints are a poor predictor of the effort needed to evaluate a patient; however, deep-learning techniques show promise. These algorithms have the potential to provide many practical applications, including balancing workloads and compensation between emergency physicians, quantify crowding and mobilizing resources, and reducing bias in the triage process.


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      • “Machine Learning as an Adjunct to Traditional Triage in the Emergency Department”
        Journal of Emergency Medicine
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          There are many applications of artificial intelligence (AI) in medicine, however, few clinicians have familiarity or experience with them. Machine learning, a subset of AI is the use of computers to “learn” and improve performance based on data provided without programming.1 Data is analyzed based on labeled outcomes in so-called supervised learning. Deep learning is computationally more complex and is said to mimic the human brain with interactions involving artificial neural networks. These methods suffer from a “black box” phenomenon that are poorly understood by clinicians, other than those who have a strong knowledge of computer science.
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