Principal Investigator

Professor of Medicine (Biomedical Informatics), of Biomedical Data Science, of Surgery and, by courtesy, of Epidemiology and Population Health

Bio

Dr. Hernandez-Boussard is an Associate Dean of Research and Professor of Medicine (Biomedical Informatics), Biomedical Data Sciences, Surgery and Epidemiology & Population Health (by courtesy) at Stanford University. With a rich background and vast expertise in biomedical informatics, health services research, and epidemiology, she is at the forefront of advancing healthcare through the development, evaluation and application of innovative methods. Through her research, she aims to effectively monitor, measure, and predict equitable healthcare outcomes. By leveraging diverse data sources, her team works diligently to construct a solid body of evidence that can significantly enhance patient outcomes, streamline healthcare delivery, and provide valuable guidance for health policy decisions. In addition, Dr. Hernandez-Boussard places significant emphasis on addressing bias and promoting fairness in AI for healthcare. Through her research and evaluation of AI technology, she seeks to advance healthcare practices while ensuring that diverse populations receive equitable resources, care, and outcomes.

Publications

  • Promoting Equity In Clinical Decision Making: Dismantling Race-Based Medicine. Health affairs (Project Hope) Hernandez-Boussard, T., Siddique, S. M., Bierman, A. S., Hightower, M., Burstin, H. 2023; 42 (10): 1369-1373

    Abstract

    As the use of artificial intelligence has spread rapidly throughout the US health care system, concerns have been raised about racial and ethnic biases built into the algorithms that often guide clinical decision making. Race-based medicine, which relies on algorithms that use race as a proxy for biological differences, has led to treatment patterns that are inappropriate, unjust, and harmful to minoritized racial and ethnic groups. These patterns have contributed to persistent disparities in health and health care. To reduce these disparities, we recommend a race-aware approach to clinical decision support that considers social and environmental factors such as structural racism and social determinants of health. Recent policy changes in medical specialty societies and innovations in algorithm development represent progress on the path to dismantling race-based medicine. Success will require continued commitment and sustained efforts among stakeholders in the health care, research, and technology sectors. Increasing the diversity of clinical trial populations, broadening the focus of precision medicine, improving education about the complex factors shaping health outcomes, and developing new guidelines and policies to enable culturally responsive care are important next steps.

    View details for DOI 10.1377/hlthaff.2023.00545

    View details for PubMedID 37782875

  • A Bayesian approach to predictive uncertainty in chemotherapy patients at risk of acute care utilization. EBioMedicine Fanconi, C., de Hond, A., Peterson, D., Capodici, A., Hernandez-Boussard, T. 2023; 92: 104632

    Abstract

    BACKGROUND: Machine learning (ML) predictions are becoming increasingly integrated into medical practice. One commonly used method, ℓ1-penalised logistic regression (LASSO), can estimate patient risk for disease outcomes but is limited by only providing point estimates. Instead, Bayesian logistic LASSO regression (BLLR) models provide distributions for risk predictions, giving clinicians a better understanding of predictive uncertainty, but they are not commonly implemented.METHODS: This study evaluates the predictive performance of different BLLRs compared to standard logistic LASSO regression, using real-world, high-dimensional, structured electronic health record (EHR) data from cancer patients initiating chemotherapy at a comprehensive cancer centre. Multiple BLLR models were compared against a LASSO model using an 80-20 random split using 10-fold cross-validation to predict the risk of acute care utilization (ACU) after starting chemotherapy.FINDINGS: This study included 8439 patients. The LASSO model predicted ACU with an area under the receiver operating characteristic curve (AUROC) of 0.806 (95% CI: 0.775-0.834). BLLR with a Horseshoe+prior and a posterior approximated by Metropolis-Hastings sampling showed similar performance: 0.807 (95% CI: 0.780-0.834) and offers the advantage of uncertainty estimation for each prediction. In addition, BLLR could identify predictions too uncertain to be automatically classified. BLLR uncertainties were stratified by different patient subgroups, demonstrating that predictive uncertainties significantly differ across race, cancer type, and stage.INTERPRETATION: BLLRs are a promising yet underutilised tool that increases explainability by providing risk estimates while offering a similar level of performance to standard LASSO-based models. Additionally, these models can identify patient subgroups with higher uncertainty, which can augment clinical decision-making.FUNDING: This work was supported in part by the National Library Of Medicine of the National Institutes of Health under Award Number R01LM013362. The content is solely the responsibility of the authors and does not necessarily represent the official views of the National Institutes of Health.

    View details for DOI 10.1016/j.ebiom.2023.104632

    View details for PubMedID 37269570

  • Perspectives on validation of clinical predictive algorithms. NPJ digital medicine de Hond, A. A., Shah, V. B., Kant, I. M., Van Calster, B., Steyerberg, E. W., Hernandez-Boussard, T. 2023; 6 (1): 86

    View details for DOI 10.1038/s41746-023-00832-9

    View details for PubMedID 37149704

  • The AI life cycle: a holistic approach to creating ethical AI for health decisions. Nature medicine Ng, M. Y., Kapur, S., Blizinsky, K. D., Hernandez-Boussard, T. 2022

    View details for DOI 10.1038/s41591-022-01993-y

    View details for PubMedID 36163298

Academic Appointments

Associate Professor, Medicine - Biomedical Informatics Research 

Associate Professor, Biomedical Data Science

Associate Professor, Surgery - General Surgery

Member, Stanford Cancer Institute

Professional Education

M.S., Stanford University, Health Services Research (2013)

Ph.D., University Claude Bernard, Lyon 1, Computational Biology (1999)

M.P.H., Yale University, Epidemiology (1993)

B.A., University California, Irvine, Psychology (1991)

B.S., University of California, Irvine, Biology (1991)