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Variety and experience: learning and forgetting in the use of surgical devices


Management Science and Operations

Publishing details

Social Sciences Research Network

Authors / Editors

Ramdas K; Saleh K; Stern S; Liu H


Publication Year



A tremendous variety of medical devices is available to surgeons today. In this environment, a surgeon's ease in using a device version that he has never previously used has important implications for cost and quality. Further, high device variety increases the time gap between repeat uses of any particular device version by a surgeon. This can result in forgetting over time of device-version-specific knowledge. While forgetting is inevitable, the impact of such forgetting over time at the level of specific tasks has not been examined previously. We use a unique, hand-collected dataset to examine learning and forgetting in hip replacement surgery as a function of a surgeon's experience with specific surgical device versions and the time between their repeat uses. We also develop a generalizable method to correct for the left-censoring of device-version-specific experience variables that is a common problem in highly granular experience data, using MLE with simulation over unobservables conditional on observables. Even for experienced surgeons, the first use of certain component versions can result in about a 26% increase in surgery duration, hurting quality and cost. Also, with the passage of time, surgeons forget knowledge gained about the use of certain components. A three-month time gap between repeat uses of a component version in surgery can result in about a 50% drop in the time saving gained from past experience. We discuss implications for practice


Social Sciences Research Network