Prioritization of hospital laboratory orders considering cancellation probabilities

In a hospital, laboratory resources must be used efficiently since accurate and timely results of laboratory tests are critical to ensure high-quality treatment of patients. One of the challenges that hospital laboratories face is the high percentage of cancellations. A test order that is cancelled during its processing results in waste of laboratory resources (labor, materials, etc.). We develop a queuing model that prioritizes orders based on their cancellation probability and tardiness. The cancellation probability is a function of order attributes (type of test, the doctor requested the test, urgency, etc.) and can be estimated from historical data. We compare the cost and timeliness of lab orders from our prioritization scheme against those from a first-come-first- served queuing system.