Probabilistic Modeling of Exam Durations in Radiology Procedures

  • Usha Nandini RaghavanEmail author
  • Christopher S. Hall
  • Ranjith Tellis
  • Thusitha Mabotuwana
  • Christoph Wald


In this paper, we model the statistical properties of imaging exam durations using parametric probability distributions such as the Gaussian, Gamma, Weibull, lognormal, and log-logistic. We establish that in a majority of radiology procedures, the underlying distribution of exam durations is best modeled by a log-logistic distribution, while the Gaussian has the poorest fit among the candidates. Further, through illustrative examples, we show how business insights and workflow analytics can be significantly impacted by making the correct (log-logistic) versus incorrect (Gaussian) model choices.


Probability distribution Exam duration Variations in practice Simulation Scenario modeling 



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Copyright information

© Society for Imaging Informatics in Medicine 2019

Authors and Affiliations

  1. 1.Philips HealthcareAndoverUSA
  2. 2.Philips Research North AmericaCambridgeUSA
  3. 3.Lahey Hospital and Medical CenterBurlingtonUSA

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