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Using Machine Learning to Identify Health Outcomes from Electronic Health Record Data

  • Pharmacoepidemiology (S Toh, Section Editor)
  • Published:
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Abstract

Purpose of Review

Electronic health records (EHRs) contain valuable data for identifying health outcomes, but these data also present numerous challenges when creating computable phenotyping algorithms. Machine learning methods could help with some of these challenges. In this review, we discuss four common scenarios that researchers may find helpful for thinking critically about when and for what tasks machine learning may be used to identify health outcomes from EHR data.

Recent Findings

We first consider the conditions in which machine learning may be especially useful with respect to two dimensions of a health outcome: (1) the characteristics of its diagnostic criteria and (2) the format in which its diagnostic data are usually stored within EHR systems. In the first dimension, we propose that for health outcomes with diagnostic criteria involving many clinical factors, vague definitions, or subjective interpretations, machine learning may be useful for modeling the complex diagnostic decision-making process from a vector of clinical inputs to identify individuals with the health outcome. In the second dimension, we propose that for health outcomes where diagnostic information is largely stored in unstructured formats such as free text or images, machine learning may be useful for extracting and structuring this information as part of a natural language processing system or an image recognition task. We then consider these two dimensions jointly to define four common scenarios of health outcomes. For each scenario, we discuss the potential uses for machine learning—first assuming accurate and complete EHR data and then relaxing these assumptions to accommodate the limitations of real-world EHR systems. We illustrate these four scenarios using concrete examples and describe how recent studies have used machine learning to identify these health outcomes from EHR data.

Summary

Machine learning has great potential to improve the accuracy and efficiency of health outcome identification from EHR systems, especially under certain conditions. To promote the use of machine learning in EHR-based phenotyping tasks, future work should prioritize efforts to increase the transportability of machine learning algorithms for use in multi-site settings.

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Acknowledgments

We thank Dr. Lisa Herrinton from the Kaiser Permanente Division of Research, Northern California for reviewing this paper and providing valuable feedback. We also thank Jacqueline Cellini from the Countway Library of Medicine for her help in identifying references for this review paper. Dr. Wong and Dr. Murray Horwitz are supported by the Thomas O. Pyle Fellowship from Harvard Medical School & Harvard Pilgrim Health Care Institute. Dr. Li is partially supported by the Agency for Healthcare Research and Quality (R01HS022728, R01HS025375, and R01HS024264). Dr. Toh is partially supported by the National Institute of Biomedical Imaging and Bioengineering (U01EB023683).

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Correspondence to Jenna Wong.

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Mara Murray Horwitz reports other from Harvard Medical School and Harvard Pilgrim Health Care Institute, during the conduct of the study. Sengwee Toh reports grants from National Institute of Biomedical Imaging and Bioengineering, during the conduct of the study. Jenna Wong reports other from Harvard Medical School and Harvard Pilgrim Health Care Institute, during the conduct of the study. Li Zhou reports grants from Agency for Healthcare Research and Quality, during the conduct of the study.

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This article does not contain any studies with human or animal subjects performed by the authors.

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Wong, J., Murray Horwitz, M., Zhou, L. et al. Using Machine Learning to Identify Health Outcomes from Electronic Health Record Data. Curr Epidemiol Rep 5, 331–342 (2018). https://doi.org/10.1007/s40471-018-0165-9

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