Jennifer Clark Nelson, PhD


“As national statistical leaders, we promote the use of rigorous methods that enhance drug and vaccine safety monitoring in the United States.”

Jennifer Clark Nelson, PhD

Director, Biostatistics; Senior Investigator, Kaiser Permanente Washington Health Research Institute
Affiliate Professor of Biostatistics, University of Washington


Jennifer Clark Nelson, PhD, is a senior investigator and biostatistician with expertise in methods to assess drug and vaccine safety and effectiveness for studies that use electronic health care data.

Dr. Nelson provides national statistical leadership and strategic direction for the U.S. Food and Drug Administration (FDA)’s Sentinel Initiative, an active surveillance system for monitoring the safety of all FDA-regulated medical products after they have reached the market. She also leads safety research within the Centers for Disease Control and Prevention (CDC)-sponsored Vaccine Safety Datalink (VSD), a national collaboration involving 13 health care organizations that has monitored immunization safety in the United States since 1990. Her CDC service further includes membership on the Advisory Committee on Immunization Practices (ACIP) COVID-19 Vaccine Safety Technical Work Group to help inform recommendations on the use of these vaccines in the U.S.

As part of both the VSD and Sentinel projects, Dr. Nelson works with her Kaiser Permanente Washington Health Research Institute (KPWHRI) colleagues Andrea Cook, PhD, and David Carrell, PhD, to pilot and scale up innovative sequential monitoring, machine learning, and natural language processing approaches that rapidly and accurately identify adverse events not detected in pre-licensure studies. Her 2013 study of the safety of a pentavalent combination DTaP-IPV-Hib (Pentacel) childhood vaccine put some of these ideas into practice and was selected as one of the American Journal of Epidemiology’s 10 best articles of the year. She and her clinical KPWHRI research partner, Lisa Jackson, MD, MPH, lead the CDC’s surveillance effort to proactively monitor the safety of the new herpes zoster vaccine for adults (Shingrix).

Dr. Nelson is an affiliate professor in biostatistics at the University of Washington (UW) and has been KPWHRI’s director of biostatistics since 2014. In collaboration with the UW, she and Dr. Cook co-founded the Seattle Symposium on Health Care Data Analytics, a conference designed to confront challenges and promote learning from electronic health record data. In 2009, Dr. Nelson earned the VSD’s Margarette Kolczak Award for outstanding contributions in biostatistics and epidemiology in vaccine safety. She is also a fellow of the American Statistical Association.

Research interests and experience

  • Biostatistics

    Post-marketing drug and vaccine safety study design and analysis; secondary use and misuse of large electronic health care databases for medical research; vaccine effectiveness study methods; sequential testing in observational data settings; methods to assess interrater variability

  • Vaccines & Infectious Diseases

    Biostatistics; post-marketing vaccine safety study design and analysis; influenza vaccine effectiveness in the elderly; methodological issues in large multi-site health care database studies

  • Medication Use & Patient Safety

    Biostatistics; post-marketing drug and vaccine safety study design and analysis; safety signal detection methods; methodological issues in large, multi-site health care database studies

  • Aging & Dementia

    Biostatistics; statistical issues in longitudinal observational cohort studies

  • Cardiovascular Health

Recent publications

Daley MF, Reifler LM, Shoup JA, Glanz JM, Lewin BJ, Klein NP, Kharbanda EO, McLean HQ, Hambidge SJ, Nelson JC, Naleway AL, Weintraub ES, McNeil MM, Razzaghi H, Singleton JA. Influenza vaccination accuracy among adults: Self-report compared with electronic health record data.  Vaccine. 2024;42(11):2740-2746. doi: 10.1016/j.vaccine.2024.03.052. Epub 2024 Mar 25. PubMed

Williams JTB, Kurlandsky K, Breslin K, Durfee MJ, Stein A, Hurley L, Shoup JA, Reifler LM, Daley MF, Lewin BJ, Goddard K, Henninger ML, Nelson JC, Vazquez-Benitez G, Hanson KE, Fuller CC, Weintraub ES, McNeil MM, Hambidge SJ. Attitudes toward COVID-19 vaccines among pregnant and recently pregnant individuals. JAMA Netw Open. 2024;7(4):e245479. doi: 10.1001/jamanetworkopen.2024.5479.  PubMed

Wyss R, van der Laan M, Gruber S, Shi X, Lee H, Dutcher SK, Nelson JC, Toh S, Russo M, Wang SV, Desai RJ, Lin KJ. Targeted learning with an undersmoothed lasso propensity score model for large-scale covariate adjustment in healthcare database studies. Am J Epidemiol. 2024 Mar 21:kwae023. doi: 10.1093/aje/kwae023. [Epub ahead of print]. PubMed

Mossa-Basha M, Andre JB, Yuh E, Hunt D, LaPiana N, Howlett B, Krakauer C, Crane P, Nelson J, DeZelar M, Meyers K, Larson E, Ralston J, Mac Donald CL. Comparison of brain imaging and physical health between research and clinical neuroimaging cohorts of ageing.  Br J Radiol. 2024;97(1155):614-621. doi: 10.1093/bjr/tqae004.  PubMed

Desai RJ, Wang SV, Sreedhara SK, Zabotka L, Khosrow-Khavar F, Nelson JC, Shi X, Toh S, Wyss R, Patorno E, Dutcher S, Li J, Lee H, Ball R, Dal Pan G, Segal JB, Suissa S, Rothman KJ, Greenland S, HernĂ¡n MA, Heagerty PJ, Schneeweiss S. Process guide for inferential studies using healthcare data from routine clinical practice to evaluate causal effects of drugs (PRINCIPLED): considerations from the FDA Sentinel Innovation Center. BMJ. 2024;384:e076460. doi: 10.1136/bmj-2023-076460.  PubMed

Markowitz LE, Hopkins RH Jr, Broder KR, Lee GM, Edwards KM, Daley MF, Jackson LA, Nelson JC, Riley LE, McNally VV, Schechter R, Whitley-Williams PN, Cunningham F, Clark M, Ryan M, Farizo KM, Wong HL, Kelman J, Beresnev T, Marshall V, Shay DK, Gee J, Woo J, McNeil MM, Su JR, Shimabukuro TT, Wharton M, Keipp Talbot H. COVID-19 Vaccine Safety Technical (VaST) Work Group: Enhancing vaccine safety monitoring during the pandemic. Vaccine. 2024 Feb 9:S0264-410X(23)01505-0. doi: 10.1016/j.vaccine.2023.12.059. [Epub ahead of print]. PubMed

Daley MF, Reifler LM, Shoup JA, Glanz JM, Naleway AL, Nelson JC, Williams JTB, McLean HQ, Vazquez-Benitez G, Goddard K, Lewin BJ, Weintraub ES, McNeil MM, Razzaghi H, Singleton JA. Racial and ethnic disparities in influenza vaccination coverage among pregnant women in the United States: The contribution of vaccine-related attitudes. Prev Med. 2023 Nov 4;177:107751. doi: 10.1016/j.ypmed.2023.107751. Online ahead of print. PubMed

Katherine Yih W, Daley MF, Duffy J, Fireman B, McClure DL, Nelson JC, Qian L, Smith N, Vazquez-Benitez G, Weintraub E, Williams JTB, Xu S, Maro JC. Safety signal identification for COVID-19 bivalent booster vaccination using tree-based scan statistics in the Vaccine Safety Datalink. Vaccine. 2023 Aug 14;41(36):5265-5270. doi: 10.1016/j.vaccine.2023.07.010. Epub 2023 Jul 20.m PubMed

DeSilva MB, Haapala J, Vazquez-Benitez G, Boyce TG, Fuller CC, Daley MF, Getahun D, Hambidge SJ, Lipkind HS, Naleway AL, Nelson JC, Vesco KK, Weintraub ES, Williams JTB, Zerbo O, Kharbanda EO. Medically attended acute adverse events in pregnant people after coronavirus disease 2019 (COVID-19) booster vaccination. Obstet Gynecol. 2023 May 11. doi: 10.1097/AOG.0000000000005241. Online ahead of print. PubMed

Kharbanda EO, Haapala J, Lipkind HS, DeSilva M, Zhu J, Vesco KK, Daley MF, Donahue J, Getahun D, Hambidge SJ, Irving SA, Klein NP, Nelson JC, Weintraub ES, Williams JTB, Vazquez-Benitez G. COVID-19 booster vaccination in early pregnancy and spontaneous abortion. JAMA Netw Open. 2023 May 1;6(5):e2314350. doi: 10.1001/jamanetworkopen.2023.14350. PubMed


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