I apply methods from operations research, epidemiology, machine learning and economics to model healthcare decisions. My work aims to inform clinical practice and health policy. I've evaluated interventions in gastroenterology and developed tools to detect and manage kidney disease in children. My dissertation focuses on the safe collection and transfusion of donated blood.

I am a PhD candidate in Management Science & Engineering at Stanford University. For the 2019-20 academic year, I am visiting McGill University as a graduate research trainee in Clinical & Health Informatics.

All Publications

  • Cost Effectiveness of Endoscopic Resection vs Transanal Resection of Complex Benign Rectal Polyps. Clinical gastroenterology and hepatology : the official clinical practice journal of the American Gastroenterological Association Yu, J. X., Russell, W. A., Ching, J. H., Kim, N., Bendavid, E., Owens, D. K., Kaltenbach, T. 2019


    BACKGROUND & AIMS: Complex benign rectal polyps can be managed with transanal surgery or with endoscopic resection (ER). Though the complication rate after ER is lower than transanal surgery, recurrence is higher. Patients lost to follow up after ER might therefore be at increased risk for rectal cancer. We evaluated the costs, benefits, and cost effectiveness of ER compared to 2 surgical techniques for removing complex rectal polyps, using a 50-year time horizon-this allowed us to capture rates of cancer development among patients lost from follow-up surveillance.METHODS: We created a Markov model to simulate the lifetime outcomes and costs of ER, transanal endoscopic microsurgery (TEM), and transanal minimally invasive surgery (TAMIS) for the management of a complex benign rectal polyp. We assessed the effect of surveillance by allowing a portion of the patients to be lost to follow up. We calculated the cost, quality-adjusted life years (QALYs), and incremental cost-effectiveness ratio or each intervention over a 50-year time horizon.RESULTS: We found that TEM was slightly more effective than TAMIS and ER (TEM, 19.54 QALYs; TAMIS, 19.53 QALYs; and ER19.53, QALYs), but ER had a lower lifetime discounted cost (ER cost $7161, TEM cost $10,459, and TAMIS cost $11,253). TEM was not cost effective compared to ER, with an incremental cost-effectiveness ratio of $485,333/QALY. TAMIS was ruled out by extended dominance. TEM became cost effective when the mortality from ER exceeded 0.63%, or if loss to follow up exceeded 25.5%.CONCLUSIONS: Using a Markov model, we found that ER, TEM, and TAMIS have similar effectiveness, but ER is less expensive, in management of benign rectal polyps. As the rate of loss to follow up increases, transanal surgery becomes more effective relative to ER.

    View details for PubMedID 30849517

  • Screening the Blood Supply for Zika Virus in the 50 U.S. States and Puerto Rico: A Cost-Effectiveness Analysis. Annals of internal medicine Russell, W. A., Stramer, S. L., Busch, M. P., Custer, B. 2019


    In 2016, universal individual donation nucleic acid testing (ID-NAT) of donated blood for Zika virus began in U.S. states and territories.To assess the cost-effectiveness of universal ID-NAT in the first year of screening compared with alternatives for the 50 states and separately for Puerto Rico.Microsimulation that captured Zika-related harms to transfusion recipients, sexual partners, and their infants.National testing results compiled by AABB and costs, utilities, and outcome probabilities estimated from the literature.Transfusion recipients.Lifetime.Societal.Universal ID-NAT, universal mini-pool NAT (MP-NAT), and ID-NAT exclusively for components transfused to women of childbearing age. Seasonally targeted strategies in Puerto Rico and geographically targeted strategies in the 50 states were also considered.Costs, quality-adjusted life-years (QALYs), and outcomes.In Puerto Rico, MP-NAT exclusively during high mosquito season was cost-effective at $81 123 per QALY (95% CI, -$49 138 to $978 242 per QALY). No screening policy was cost-effective in the 50 states. Universal ID-NAT cost $341 million per QALY (CI, $125 million to $2.90 billion per QALY) compared with no screening in the 50 states.In Puerto Rico, MP-NAT only during the season of high mosquito activity was most cost-effective in 64% of probabilistic sensitivity analysis iterations. In the 50 states, no intervention was cost-effective in 99.99% of iterations. Cost-effectiveness was highly dependent on the rate of assumed infectious donations.Data were limited on the component-specific transmissibility of Zika and long-term sequelae of infection.Screening was cost-effective only in the high mosquito season in Puerto Rico, and no evaluated screening policy was cost-effective in the 50 states. During periods with lower rates of Zika-infectious donations, the cost-effectiveness of screening will be even less favorable.None.

    View details for PubMedID 30615781