Clinical Focus

  • Family Medicine
  • general adult medicine and seniors
  • LGBTQ Friendly

Academic Appointments

Administrative Appointments

  • Associate Dean for Primary Care & Population Health, Stanford School of Medicine (2012 - Present)
  • Division Chief, Primary Care and Population Health, Department of Medicine (2016 - Present)

Professional Education

  • Residency: UCSF Family Medicine Residency (1990) CA
  • Medical Education: University of California at San Francisco School of Medicine (1987) CA
  • Board Certification: American Board of Family Medicine, Family Medicine (1991)
  • MPH, University of California, Berkeley, Public Health (2007)
  • BA, Harvard College, Psychology (1982)

2023-24 Courses

All Publications

  • A value-based approach to optimize red blood cell transfusion in patients receiving extracorporeal membrane oxygenation. Perfusion Shudo, Y., Cheng, N., He, H., Rosenberg, C., Hiesinger, W., Hadhazy, E., Shepard, J., Krishna, P., Resnik, J., Fong, R., Hill, C., Hsu, J. L., Maggio, P. M., Chang, S., Boyd, J. H., Woo, Y. J. 2022: 2676591221128138


    INTRODUCTION: The risk, cost, and adverse outcomes associated with packed red blood cell (RBC) transfusions in patients with cardiopulmonary failure requiring extracorporeal membrane oxygenation (ECMO) have raised concerns regarding the overutilization of RBC products. It is, therefore, necessary to establish optimal transfusion criteria and protocols for patients supported with ECMO. The goal of this study was to establish specific criteria for RBC transfusions in patients undergoing ECMO.METHODS: This was a retrospective cohort study conducted at Stanford University Hospital. Data on RBC utilization during the entire hospital stay were obtained, which included patients aged ≥18years who received ECMO support between 1 January 2017, and 30 June 2020 (n = 281). The primary outcome was in-hospital mortality.RESULTS: Hemoglobin (HGB) levels >10g/dL before transfusion did not improve in-hospital survival. Therefore, we revised the HGB threshold to ≤10g/dL to guide transfusion in patients undergoing ECMO. To validate this intervention, we prospectively compared the pre- and post-intervention cohorts for in-hospital mortality. Post-intervention analyses found 100% compliance for all eligible records and a decrease in the requirement for RBC transfusion by 1.2 units per patient without affecting the mortality.CONCLUSIONS: As an institution-driven value-based approach to guide transfusion in patients undergoing ECMO, we lowered the threshold HGB level. Validation of this revised intervention demonstrated excellent compliance and reduced the need for RBC transfusion while maintaining the clinical outcome. Our findings can help reform value-based healthcare in this cohort while maintaining the outcome.

    View details for DOI 10.1177/02676591221128138

    View details for PubMedID 36148806

  • Case-control study evaluating risk factors for SARS-CoV-2 outbreak amongst healthcare personnel at a tertiary care center. American journal of infection control Rosser, J. I., Tayyar, R., Giardina, R., Kolonoski, P., Kenski, D., Shen, P., Steinmetz, L. M., Hung, L., Xiao, W., Bains, K., Morrison, T., Madison, A., Chang, S., Tompkins, L., Pinsky, B. A., Holubar, M. 2021


    BACKGROUND: Despite several outbreaks of SARS-CoV-2 amongst healthcare personnel (HCP) exposed to COVID-19 patients globally, risk factors for transmission remain poorly understood.METHODS: We conducted an outbreak investigation and case-control study to evaluate SARS-CoV-2 transmission risk in an outbreak among HCP at an academic medical center in California that was confirmed by whole genome sequencing.RESULTS: A total of 7/9 cases and 93/182 controls completed a voluntary survey about risk factors. Compared to controls, cases reported significantly more patient contact time. Cases were also significantly more likely to have performed airway procedures on the index patient, particularly placing the patient on high flow nasal cannula, continuous positive airway pressure (CPAP), or bilevel positive airway pressure (BiPAP) (OR=11.6; 95% CI=1.7-132.1).DISCUSSION: This study highlights the risk of nosocomial infection of SARS-CoV-2 from patients who become infectious midway into their hospitalization. Our findings also reinforce the importance of patient contact and aerosol-generating procedures as key risk factors for HCP infection with SARS-CoV-2.CONCLUSIONS: Re-testing patients for SARS-CoV-2 after admission in suspicious cases and using N95 masks for all aerosol-generating procedures regardless of initial patient SARS-CoV-2 test results can help reduce the risk of SARS-COV-2 transmission to HCP.

    View details for DOI 10.1016/j.ajic.2021.09.004

    View details for PubMedID 34536502

  • Building Bridges Between Community Health Centers and Academic Medical Centers in a COVID-19 Pandemic. Journal of the American Board of Family Medicine : JABFM Taylor, N. K., Aboelata, N., Mahoney, M., Seay-Morrison, T., Singh, B., Chang, S., Asch, S. M., Shaw, J. G. 2021; 34 (Supplement): S229–S232


    The threat to the public health of the United States from the COVID-19 pandemic is causing rapid, unprecedented shifts in the health care landscape. Community health centers serve the patient populations most vulnerable to the disease yet often have inadequate resources to combat it. Academic medical centers do not always have the community connections needed for the most effective population health approaches. We describe how a bridge between a community health center partner (Roots Community Health Center) and a large academic medical center (Stanford Medicine) brought complementary strengths together to address the regional public health crisis. The 2 institutions began the crisis with an overlapping clinical and research faculty member (NKT). Building on that foundation, we worked in 3 areas. First, we partnered to reach underserved populations with the academic center's newly developed COVID test. Second, we developed and distributed evidence-based resources to these same communities via a large community health navigator team. Third, as telemedicine became the norm for medical consultation, the 2 institutions began to research how reducing the digital divide could help improve access to care. We continue to think about how best to create enduring partnerships forged through ongoing deeper relationships beyond the pandemic.

    View details for DOI 10.3122/jabfm.2021.S1.200182

    View details for PubMedID 33622844

  • The prevalence of COVID-19 in healthcare personnel in an adult and pediatric academic medical center. American journal of infection control Shepard, J., Kling, S. M., Lee, G., Wong, F., Frederick, J., Skhiri, M., Holubar, M., Shaw, J. G., Stafford, D., Schilling, L., Kim, J., Ick Chang, S., Frush, K., Hadhazy, E. 2021; 49 (5): 542–46


    BACKGROUND: It is vital to know which healthcare personnel (HCP) have a higher chance of testing positive for severe acute respiratory syndrome coronavirus 2 (COVID-19).METHODS: A retrospective analysis was conducted at Stanford Children's Health (SCH) and Stanford Health Care (SHC) in Stanford, California. Analysis included all HCP, employed by SCH or SHC, who had a COVID-19 reverse transcriptase polymerase chain reaction (RT-PCR) test resulted by the SHC Laboratory, between March 1, 2020 and June 15, 2020. The primary outcome was the RT-PCR percent positivity and prevalence of COVID-19 for HCP and these were compared across roles.RESULTS: SCH and SHC had 24,081 active employees, of which 142 had at least 1 positive COVID-19 test. The overall HCP prevalence of COVID-19 was 0.59% and percent positivity was 1.84%. Patient facing HCPs had a significantly higher prevalence (0.66% vs 0.43%; P = .0331) and percent positivity (1.95% vs 1.43%; P = .0396) than nonpatient facing employees, respectively. Percent positivity was higher in food service workers (9.15%), and environmental services (5.96%) compared to clinicians (1.93%; P < .0001) and nurses (1.46%; P < .0001), respectively.DISCUSSION AND CONCLUSION: HCP in patient-facing roles and in support roles had a greater chance of being positive of COVID-19.

    View details for DOI 10.1016/j.ajic.2021.01.004

    View details for PubMedID 33896582

  • SARS-CoV-2 Seroprevalence in Healthcare Personnel in Northern California Early in the COVID-19 Pandemic. Infection control and hospital epidemiology Rosser, J. I., Roltgen, K., Dymock, M., Shepard, J., Martin, A., Hogan, C. A., Blomkalns, A., Mathew, R., Parsonnet, J., Pinsky, B. A., Maldonado, Y. A., Boyd, S. D., Chang, S., Holubar, M., Stanford Healthcare COVID-19 Workforce Response Group 2020: 1–27


    OBJECTIVE: We aimed to assess the magnitude of unidentified SARS-CoV-2 infections in our healthcare personnel (HCP) early in the COVID-19 pandemic and evaluate risk factors for infection in order to identify areas for infection control practice improvement in a northern California academic medical center.METHODS: We reviewed the anti-SARS-CoV-2 receptor binding domain (RBD) IgG serologic test results and self-reported risk factors for seropositivity among 10,449 asymptomatic HCP who underwent voluntary serology testing between April 20 and May 20, 2020.RESULTS: In total, 136 employees (1.3%) tested positive for SARS-CoV-2 IgG. This included 41 (30.1%) individuals who had previously tested positive for SARS-CoV-2 by nasopharyngeal reverse transcription polymerase chain reaction (RT-PCR) between March 13 and April 16, 2020. In multivariable analysis, employees of Hispanic ethnicity (OR = 2.01; 95% CI = 1.22-3.46) and those working in environmental services/food services/patient transport (OR = 4.81; 95% CI = 2.08-10.30) were at increased risk for seropositivity compared to other groups. Employees reporting a household contact with COVID-19 were also at higher risk for seropositivity (OR = 3.25; 95% CI = 1.47-6.44), but those with a work exposure were not (OR = 1.27; 95% CI = 0.58-2.47). Importantly, one-third of seropositive individuals reported no prior symptoms, no suspected exposures, and no prior positive RT-PCR test.CONCLUSION: In this study, SARS-CoV-2 seropositivity among HCP early in the northern California epidemic appeared to be quite low and was more likely attributable to community rather than occupational exposure.

    View details for DOI 10.1017/ice.2020.1358

    View details for PubMedID 33292895

  • Large-Scale Testing of Asymptomatic Healthcare Personnel for Severe Acute Respiratory Syndrome Coronavirus 2. Emerging infectious diseases Hogan, C. A., Gombar, S. n., Wang, H. n., Röltgen, K. n., Shi, R. Z., Holubar, M. n., Chang, S. I., Lee, G. M., Boyd, S. D., Zehnder, J. n., Pinsky, B. A. 2020; 27 (1)


    Large-scale, 1-time testing of >12,000 asymptomatic healthcare personnel in California, USA, during April-June 2020 showed that prevalence of severe acute respiratory syndrome coronavirus 2 was low (<1%). Testing might identify asymptomatic and presymptomatic persons, including some with high viral burden, enabling prompt implementation of measures to limit nosocomial spread.

    View details for DOI 10.3201/eid2701.203892

    View details for PubMedID 33256889

  • Primary Care 2.0: Design of a Transformational Team-Based Practice Model to Meet the Quadruple Aim AMERICAN JOURNAL OF MEDICAL QUALITY Brown-Johnson, C. G., Chan, G. K., Winget, M., Shaw, J. G., Patton, K., Hussain, R., Olayiwola, J., Chang, S., Mahoney, M. 2019; 34 (4): 339–47
  • Primary Care 2.0: Design of a Transformational Team-Based Practice Model to Meet the Quadruple Aim. American journal of medical quality : the official journal of the American College of Medical Quality Brown-Johnson, C. G., Chan, G. K., Winget, M., Shaw, J. G., Patton, K., Hussain, R., Olayiwola, J. N., Chang, S., Mahoney, M. 2018: 1062860618802365


    A new transformational model of primary care is needed to address patient care complexity and provider burnout. An 18-month design effort (2015-2016) included the following: (1) Needs Finding, (2) Integrated Facility Design, (3) Design Process Assessment, and (4) Development of Evaluation. Initial outcome metrics were assessed. The design team successfully applied Integrated Facility Design to primary care transformation design; qualitative survey results suggest that design consensus was facilitated by team-building activities. Initial implementation of Quadruple Aim-related outcome metrics showed positive trends. Redesign processes may benefit from emphasis on team building to facilitate consensus and increased patient involvement to incorporate patient voices successfully.

    View details for PubMedID 30409021

  • Patient and provider perspectives on the development of personalized medicine: a mixed-methods approach JOURNAL OF COMMUNITY GENETICS Puryear, L., Downs, N., Nevedal, A., Lewis, E. T., Ormond, K. E., Bregendahl, M., Suarez, C. J., David, S. P., Charlap, S., Chu, I., Asch, S. M., Pakdaman, N., Chang, S., Cullen, M. R., Palaniappan, L. 2018; 9 (3): 283–91
  • Patient and provider perspectives on the development of personalized medicine: a mixed-methods approach. Journal of community genetics Puryear, L. n., Downs, N. n., Nevedal, A. n., Lewis, E. T., Ormond, K. E., Bregendahl, M. n., Suarez, C. J., David, S. P., Charlap, S. n., Chu, I. n., Asch, S. M., Pakdaman, N. n., Chang, S. I., Cullen, M. R., Palaniappan, L. n. 2017


    While genetic testing gains adoption in specialty services such as oncology, neurology, and cardiology, use of genetic and genomic testing has yet to be adopted as widely in primary care. The purpose of this study is to identify and compare patient and primary care provider (PCP) expectations of genetics services in primary care. Patient and PCP perspectives were assessed through a mixed-method approach combining an online survey and semi-structured interviews in a primary care department of a large academic medical institution. A convenience sample of 100 adult primary care patients and 26 PCPs was gathered. The survey and interview questions focused on perceptions of genetic testing, experience with genetic testing, and expectations of genetic services in primary care. Patients felt that their PCP was knowledgeable about genetic testing and expected their PCP to be the first to recognize a need for genetic testing based on family history. Nonetheless, patients reported that PCPs rarely used family history information to discuss genetic risks or order testing. In contrast, PCPs felt uncertain about the clinical utility and scientific value of genetic testing. PCPs were concerned that genetic testing could cause anxiety, frustration, discrimination, and reduced insurability, and that there was unequal access to testing. PCPs described themselves as being "gatekeepers" to genetic testing but did not feel confident or have the desire to become experts in genetic testing. However, PCPs were open to increasing their working knowledge of genetic testing. Within this academic medical center, there is a gap between what patients expect and what primary care providers feel they are adequately prepared to provide in terms of genetic testing services.

    View details for PubMedID 29280052