Clinical Focus

  • Internal Medicine
  • Primary Care
  • Preventive Health
  • Diabetes Mellitus

Academic Appointments

Honors & Awards

  • Paul Dudley White Traveling Fellowship, Harvard University (2006)
  • Harvard Presidential Scholars Public Service Initiative Award, Harvard University (2006)
  • Center for Health Quality and Innovation Fellowship, University of California, Office of the President (2012)

Boards, Advisory Committees, Professional Organizations

  • Member, Society of General Internal Medicine (2007 - Present)
  • Member, American College of Physicians (2007 - Present)

Professional Education

  • Residency: Massachusetts General Hospital Internal Medicine Residency MA
  • Internship: Massachusetts General Hospital Internal Medicine Residency MA
  • Medical Education: Harvard Medical School MA
  • Board Certification: Internal Medicine, American Board of Internal Medicine (2009)
  • AB, Princeton University, Public and International Affairs (health policy)

Community and International Work

  • Medical tent volunteer at San Francisco-based marathons and half-marathons

    Partnering Organization(s)

    UCSF Sports Medicine


    Bay Area

    Ongoing Project


    Opportunities for Student Involvement



All Publications

  • Variability in hospital costs for carotid artery revascularization. Journal of vascular surgery Mell, M. W., Tang, N., Lew, R., Dalman, R. L. 2018


    OBJECTIVE: The objective of this study was to understand drivers of cost for carotid endarterectomy (CEA) and carotid artery stenting (CAS) and to compare variation in cost among cases performed by vascular surgery (VS) with other services (OSs).METHODS: We collected internal hospital claims data for CEA and CAS between September 2013 and August 2015 and performed a financial analysis of all hospital costs including room accommodations, medications, medical and surgical supplies, imaging, and laboratory tests. Cases were stratified by presence of symptoms and procedure type, and costs of procedures performed by VS were compared with those performed by OSs.RESULTS: The cohort comprised 144 patients (78 asymptomatic, 66 symptomatic; 44 CAS, 100 CEA) receiving unilateral revascularization. VS (24 CAS, 70 CEA) and neurosurgery and neurointerventional radiology services (20 CAS, 30 CEA) performed all procedures. Age (71 9years vs 70 11years; P= .8) and length of stay (1.7 2.1days vs 2.2 2.4days; P=.73) were similar for VS and OSs. Symptoms were present before revascularization for 46% and were more commonly treated by OSs (78% vs 29%; P< .001). Case mix index was similar after stratifying by symptoms (asymptomatic, 1.280.35 vs 1.39 0.42 [P= .5]; symptomatic, 1.66 0.73 vs 1.82 0.81 [P= .9]). The largest cost components were operating room (OR)-related costs, beds, and supplies, together accounting for 76% of costs. Asymptomatic patients had 37% lower average hospital costs. For asymptomatic CAS, average index hospitalization cost was 17% less for VS compared with OSs because of 78% lower intensive care unit costs, 44% lower OR-related costs, 40% lower medication costs, and 24% lower cardiac testing costs. VS had 22% higher supply costs. For asymptomatic CEA, average index hospitalization costs were 22% lower for VS, driven by lower OR-related costs (28%), medications (28%), imaging (62%), and neurointerventional monitoring (64%). Costs were 38% higher for CAS vs CEA. For symptomatic CAS, costs were similar for both groups. For symptomatic CEA, total costs were 14% lower for VS compared with OSs, driven by 25% lower OR-related costs, 62% lower neurointerventional monitoring, 20% step-down beds, and 28% lower supply costs (and counterbalanced by 117% higher intensive care unit costs).CONCLUSIONS: VS average hospital costs were lower for asymptomatic CAS and all CEAs compared with OSs. Drivers of higher cost appear to be attributed to variation in physicians' practice as well as patients' complexity, affording an opportunity to reduce cost by establishing standard practices when appropriate.

    View details for PubMedID 30197159

  • Episode-based cost reduction for endovascular aneurysm repair. Journal of vascular surgery Itoga, N. K., Tang, N., Patterson, D., Ohkuma, R., Lew, R., Mell, M. W., Dalman, R. L. 2018


    OBJECTIVE: Effective strategies to reduce costs associated with endovascular aneurysm repair (EVAR) remain elusive for many medical centers. In this study, targeted interventions to reduce inpatient EVAR costs were identified and implemented.METHODS: From June 2015 to February 2016, we analyzed the EVAR practice at a high-volume academic medical center to identify, to rank, and ultimately to reduce procedure-related costs. In this analysis, per-patient direct costs to the hospital were compared before (September 2013-May 2015) and after (March 2016-January 2017) interventions were implemented. Improvement efforts concentrated on three categories that accounted for a majority of costs: implants, rooming costs, and computed tomography scans performed during the index hospitalization.RESULTS: Costs were compared between 141 EVAR procedures before implementation (PRE period) and 47 EVAR procedures after implementation (POST period). Based on data obtained through the Society for Vascular Surgery EVAR Cost Demonstration Project, it was determined that implantable device costs were higher than those at peer institutions. New purchasing strategies were implemented, resulting in a 30.8% decrease in per-case device costs between the PRE and POST periods. Care pathways were modified to reduce use of and costs for computed tomography scans obtained during the index hospitalization. Compared with baseline, per-case imaging costs decreased by 92.9% (P< .001), including a 99.0% (P= .001) reduction in postprocessing costs. Care pathways were also implemented to reduce preprocedural rooming for patients traveling long distances the day before surgery, resulting in a 50% decrease in utilization rate (35.4% PRE to 17.0% POST; P= .021), without having a significant impact on median postprocedural length of stay (PRE, 2days [interquartile range, 1-11days]; POST, 2days [1-7days]; P= .185). Medication costs also decreased by 38.2% (P< .001) as a hospital-wide effort.CONCLUSIONS: Excessive costs associated with EVAR threaten the sustainability of these procedures in health care organizations. Targeted cost reduction efforts can effectively reduce expenses without compromising quality or limiting patients' access.

    View details for PubMedID 30185384

  • Episode-Based Cost Reduction for Endovascular Aneurysm Repair Dalman, R. L., Tang, N., Patterson, D., Jolly, H., Ohkuma, R., Mell, M. W. MOSBY-ELSEVIER. 2017: E58
  • Variability in Hospital Costs for Carotid Artery Revascularization Mell, M. W., Tang, N., Patterson, D., Sigurdsson, S., Kell, C., Jolly, H., Lew, R., Dalman, R. L. MOSBY-ELSEVIER. 2017: 7S
  • Evaluation of a Primary Care-Based Post-Discharge Phone Call Program: Keeping the Primary Care Practice at the Center of Post-hospitalization Care Transition JOURNAL OF GENERAL INTERNAL MEDICINE Tang, N., Fujimoto, J., Karliner, L. 2014; 29 (11): 1513-1518


    The post-hospitalization period is a precarious time for patients. Post-discharge nurse telephone call programs aiming to prevent unnecessary readmissions have had mixed results.Describe a primary-care based program to identify and address problems arising after hospital discharge.A quality improvement program embedding registered nurses in a primary care practice to call patients within 72 h of hospital discharge and route problems within the practice for real-time resolution.Adult patients with a primary care provider in the general internal medicine practice at the University of California San Francisco who were discharged home from the Medicine service.Patients reached directly by phone had a 'full-scripted encounter;' those reached only by voice-mail had a 'message-scripted encounter;' those not reached despite multiple attempts had a 'missed encounter.' Among patients with full-scripted encounters, we identified and cataloged problems arising after hospital discharge and measured the proportion of calls in which a problem was uncovered. For the different encounter types, we compared follow-up appointment attendance and 30-day readmission rates.Of 790 eligible discharges, 486 had a full-scripted, 229 a message-scripted and 75 a missed encounter. Among the 486 full-scripted encounters, nurses uncovered at least one problem in 371 (76 %) discharges, 25 % of which (n?=?94) included new symptoms, and 47 % (n?=?173) included medication issues. Discharges with full-scripted and message-scripted encounters were associated with higher follow-up appointment attendance rates compared with those with missed encounters (60.1 %, 58.5 %, 38.5 % respectively p?=?0.004). There was no significant difference in 30-day readmission rates (12.8 %, 14.8 %, 14.7 %; p?=?0.72).Our results suggest that centering a post-discharge phone call program within the primary care practice improves post-hospital care by identifying clinical and care-coordination problems early. With the new Medicare transitional care payment, such programs could become an important, self-sustaining part of the patient-centered medical home.

    View details for DOI 10.1007/s11606-014-2942-6

    View details for Web of Science ID 000344077900019

    View details for PubMedID 25055997

  • Variations in 30-Day Hospital Readmission Rates Across Primary Care Clinics Within a Tertiary Referral Center JOURNAL OF HOSPITAL MEDICINE Tang, N., Maselli, J. H., Gonzales, R. 2014; 9 (11): 688-694


    Reducing hospital readmissions is a national healthcare priority. Little is known about how readmission rates vary across unique primary care practices.To calculate all-cause 30-day hospital readmission rates at the level of individual primary care practices and identify factors associated with variations in these rates.Retrospective analysisSeven primary care clinics affiliated with the University of California, San Francisco (UCSF).Adults ?18 years old with a primary care provider (PCP) at UCSF MEASUREMENTS: All-cause 30-day readmission rates were calculated for primary care clinics for discharges between July 1, 2009 and June 30, 2012. We built a model to identify demographic, clinical, and hospital factors associated with variation in rates.There were 12,564 discharges for patients belonging to the 7 clinics, with 8685 index discharges and 1032 readmissions. Readmission rates varied across practices, from 14.9% in Human Immunodeficiency Virus primary care and 7.7% in women's health. In multivariable analyses, factors associated with variation in readmission rates included: male gender (odds ratio [OR]: 1.21, 95% confidence interval [CI]: 1.05-1.40), Medicare insurance (OR: 1.31, 95% CI: 1.05, 1.64; Ref?=?private), Medicare-Medicaid dual eligible (OR: 1.26, 95% CI: 1.01-1.56), multiple comorbidities, and admitting services. Patients with a departed PCP awaiting transfer assignment to a new PCP had an OR of 1.59 (95% CI: 1.16-2.17) compared with having a current faculty PCP.Primary care practices are important partners in improving care transitions and reducing hospital readmissions, and this study introduces a new way to view readmission rates. PCP turnover may be an important risk factor for hospital readmissions.

    View details for DOI 10.1002/jhm.2243

    View details for Web of Science ID 000344457800002

    View details for PubMedID 25130292

  • What's Cost Got to Do With It? Association Between Hospital Costs and Frequency of Admissions Among "High Users" of Hospital Care JOURNAL OF HOSPITAL MEDICINE Oanh Kieu Nguyen, O. K., Tang, N., Hillman, J. M., Gonzales, R. 2013; 8 (12): 665-671


    Efforts to curb healthcare spending have included interventions that target frequently hospitalized individuals. It is unclear the extent to which the most frequently hospitalized individuals also represent the costliest individuals.To examine the relationship between 2 types of "high users" commonly targeted in cost-containment interventions-those incurring the highest hospital costs ("high cost") and those incurring the highest number of hospitalizations ("high admit").Cross-sectional study of 2566 individuals with a primary care physician and at least 1 hospitalization within an academic health system from 2010 to 2011.Overlap between the population constituting the top decile of hospital costs and the population constituting the top decile of hospitalizations; characteristics of the 3 resulting high user subgroups.Only 48% of individuals who were high cost (>$65,000) were also high admit (? 3 hospitalizations). Compared to hospitalizations incurred by high cost-high admit individuals (n = 605), hospitalizations incurred by high cost-low admit individuals (n = 206) were more likely to be for surgical procedures (58 vs 22%, P < 0.001), had a higher cost ($68,000 vs $28,000, P < 0.001), longer length of stay (10 vs 5 days, P < 0.001), and were less likely to be a 30-day readmission (17 vs 47%, P < 0.001).Stratifying high admit individuals by costs and high cost individuals by hospitalizations yields 3 distinct high user subgroups with important differences in clinical characteristics and utilization patterns. Consideration of these distinct subgroups may lead to better-tailored interventions and achieve greater cost savings.

    View details for DOI 10.1002/jhm.2096

    View details for Web of Science ID 000327999500001

    View details for PubMedID 24173680

  • A primary care physician's ideal transitions of carewhere's the evidence? JOURNAL OF HOSPITAL MEDICINE Tang, N. 2013; 8 (8): 472-477


    Reducing hospital readmissions is a national healthcare priority. Most of the interventions to reduce hospital readmission have been concentrated in the inpatient setting. However, there is increasing attention placed on the role of primary care physicians (PCPs) in improving the transition from hospital to home. In this article, a primary care physician's perspective of how inpatient and outpatient providers can partner to create the ideal care transition is described. Seven steps that occur during the hospitalization are highlighted: communicate with the PCP on admission, involve the PCP early regarding discharge planning, notify the PCP on hospital discharge, complete the discharge summary at time of discharge, schedule follow-up appointments by discharge, ensure prescriptions are available at the patient's pharmacy, and educate the patient about self-management. Another 7 are described as the role of the PCP and clinic staff: call the patient within 72 hours of discharge, ensure follow-up appointments with the PCP, coordinate care, repeat above until medically stable, create access for patients with new symptoms, track readmission rates, and track and review frequently admitted patients. Insights are offered on how the changing financial landscape can help support elements of this idealized transition-of-care program.

    View details for DOI 10.1002/jhm.2060

    View details for Web of Science ID 000322791400010

    View details for PubMedID 23873732

  • Ambulatory Patient Safety: The Time Is Now: Comment on "Patient Perceptions of Mistakes in Ambulatory Care" ARCHIVES OF INTERNAL MEDICINE Tang, N., Meyer, G. S. 2010; 170 (16): 1487-1489
  • Trends and Characteristics of US Emergency Department Visits, 1997-2007 JAMA-JOURNAL OF THE AMERICAN MEDICAL ASSOCIATION Tang, N., Stein, J., Hsia, R. Y., Maselli, J. H., Gonzales, R. 2010; 304 (6): 664-670


    The potential effects of increasing numbers of uninsured and underinsured persons on US emergency departments (EDs) is a concern for the health care safety net.To describe the changes in ED visits that occurred from 1997 through 2007 in the adult and pediatric US populations by sociodemographic group, designation of safety-net ED, and trends in ambulatory care-sensitive conditions.Publicly available ED visit data from the National Hospital Ambulatory Medical Care Survey (NHAMCS) from 1997 through 2007 were stratified by age, sex, race, ethnicity, insurance status, safety-net hospital classification, triage category, and disposition. Codes from the International Classification of Diseases, Ninth Revision (ICD-9), were used to extract visits related to ambulatory care-sensitive conditions. Visit rates were calculated using annual US Census estimates.Total annual visits to US EDs and ED visit rates for population subgroups.Between 1997 and 2007, ED visit rates increased from 352.8 to 390.5 per 1000 persons (rate difference, 37.7; 95% confidence interval [CI], -51.1 to 126.5; P = .001 for trend); the increase in total annual ED visits was almost double of what would be expected from population growth. Adults with Medicaid accounted for most of the increase in ED visits; the visit rate increased from 693.9 to 947.2 visits per 1000 enrollees between 1999 and 2007 (rate difference, 253.3; 95% CI, 41.1 to 465.5; P = .001 for trend). Although ED visit rates for adults with ambulatory care-sensitive conditions remained stable, ED visit rates among adults with Medicaid increased from 66.4 in 1999 to 83.9 in 2007 (rate difference, 17.5; 95% CI, -5.8 to 40.8; P = .007 for trend). The number of facilities qualifying as safety-net EDs increased from 1770 in 2000 to 2489 in 2007.These findings indicate that ED visit rates have increased from 1997 to 2007 and that EDs are increasingly serving as the safety net for medically underserved patients, particularly adults with Medicaid.

    View details for DOI 10.1001/jama.2010.1112

    View details for Web of Science ID 000280829200022

    View details for PubMedID 20699458

  • The roles of government in improving health care quality and safety. Joint Commission journal on quality and safety Tang, N., Eisenberg, J. M., Meyer, G. S. 2004; 30 (1): 47-55


    Discussions surrounding the role of government have been and continue to be a favorite American pastime. A framework is provided for understanding the 10 roles that government plays in improving health care quality and safety in the United States. Examples of proposed federal actions to reduce medical errors and enhance patient safety are provided to illustrate the 10 roles: (1) purchase health care, (2) provide health care, (3) ensure access to quality care for vulnerable populations, (4) regulate health care markets, (5) support acquisition of new knowledge, (6) develop and evaluate health technologies and practices, (7) monitor health care quality, (8) inform health care decision makers, (9) develop the health care workforce, and (10) convene stakeholders from across the health care system.Government's responsibility to protect and advance the interests of society includes the delivery of high-quality health care. Because the market alone cannot ensure all Americans access to quality health care, the government must preserve the interests of its citizens by supplementing the market where there are gaps and regulating the market where there is inefficiency or unfairness. The ultimate goal of achieving high quality of care will require strong partnerships among federal, state, and local governments and the private sector. Translating general principles regarding the appropriate role of government into specific actions within a rapidly changing, decentralized delivery system will require the combined efforts of the public and private sectors.

    View details for PubMedID 14738036

  • The US Agency for Healthcare Research and Quality's activities in patient safety research 18th International Conference of the International-Society-for-Quality-in-Health-Care Meyer, G. S., Battles, J., Hart, J. C., Tang, N. OXFORD UNIV PRESS. 2003: I25?I30


    To update the international community on the US Agency for Healthcare Research and Quality's (AHRQ) recent and current activities in improving patient safety.Review of the literature concerning the importance of patient safety as a health care quality issue, international perspectives on patient safety, a review of research solicitations, and early results of funded studies.A representative sample of patient safety studies from those currently being funded by AHRQ.In response to a growing interest in patient safety in general and a recent US Institute of Medicine report on patient safety in particular, the US Agency for Healthcare Research and Quality has refocused its quality research mission. In the fiscal year 2002, AHRQ spent US$55 million on patient safety research. This investment was spread across six complementary research areas: (1) health systems error reporting, analysis, and safety improvement research demonstrations; (2) Clinical Informatics to Promote Patient Safety (CLIPS); (3) Centers of Excellence for patient safety research and practice (COE); (4) Developmental Centers for Evaluation and Research in Patient Safety (DCERPS); (5) The Effect of Health Care Working Conditions on Quality of Care; and (6) Partnerships for Quality: Patient Safety Research Dissemination and Education. Internal teams of researchers at AHRQ have published studies on patient safety, such as documenting the impact of medication errors. In addition to funding research on patient safety, AHRQ is an integral partner in several national and international collaborations to form strategic synergies that build upon each member organization's strengths, reduce redundant efforts, and benefit from each other's successes. As evidence on patient safety is generated, AHRQ also serves the important mission of disseminating information to the public.The patient safety research field has undergone a period of rapid evolution. It is now incumbent upon the international health care quality improvement community to translate the future results of this research investment into improved safety for patients.

    View details for DOI 10.1093/intqhc/mzg068

    View details for Web of Science ID 000187281500005

    View details for PubMedID 14660520

  • Istituto Clinico Humanitas Harvard Business School Case Study Bohmer, R., Pisano, G. P., Tang, N. 2002

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