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Black Clouds vs Random Variation in Hospital Admissions.

Luei Wern Ong1, Jeffrey D Dawson2, John W Ely3

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The "black cloud" phenomenon, where physicians have unusually high hospital admissions, is likely due to random variation, not individual physician performance. This variation impacts resident education and patient safety.

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Area of Science:

  • Medical Practice Analysis
  • Physician Performance Metrics

Background:

  • Physicians are sometimes labeled "black clouds" if they have consistently high hospital admission rates.
  • The existence of a true "black cloud" phenomenon versus random variation is debated.

Purpose of the Study:

  • To investigate whether the "black cloud" phenomenon in hospital admissions is a real effect or attributable to random chance.
  • To analyze physician admission data to identify potential "black cloud" and "white cloud" physicians.

Main Methods:

  • Analysis of hospital admissions for a family medicine service over five years (2010-2015).
  • Stratification of data by physician peer groups (e.g., attending physicians, senior residents).
  • Use of mixed-effects negative binomial regression to test for significant differences in admission numbers among physicians, controlling for confounding variables.

Main Results:

  • The study included 96 physicians and 6,194 admissions, with a notable increase in admissions over the study period.
  • Initial analysis identified potential "black cloud" and "white cloud" physicians.
  • After controlling for study year and other factors, no significant associations were found between individual physicians and admission numbers.

Conclusions:

  • Apparent "black cloud" and "white cloud" physician effects can be explained by random variation in hospital admissions.
  • This random variation leads to significant workload disparities among physicians.
  • Workload variations have potential implications for resident education and patient safety.