Sarah Walker, Professor of Medical Statistics & Epidemiology, FMedSci

Sarah has worked at the Unit since its initiation in 1999, having previously worked at the MRC HIV Clinical Trials Centre since 1994. Her work includes the design and analysis of clinical trials and observational studies of treatment and management strategies for HIV and other infectious diseases, including serious bacterial infections and Hepatitis C. She has worked on projects involving both adults and children, in high-income and low/middle-income countries. Methodological research interests include the development of novel trial designs to address problems identifying the optimal duration of antibiotic treatment (MAMS-ROCI) and where there is no single standard of care (PRACTical), as well as the use of causal models to address additional non-randomised questions using data from clinical trials. She was elected to the Academy of Medical Sciences in 2019

Since April 2006, Sarah has worked part-time at the University of Oxford with the Modernising Medical Microbiology Consortium translating new whole genome sequencing approaches into microbiology practice and service and investigating electronic health records for infectious diseases research. She is currently Director of the NIHR Health Protection Research Unit in Antimicrobial Resistance and Healthcare Associated Infections and Lead of the Modernising Microbiology and Big Infection Diagnostics Theme of the NIHR Biomedical Research Centre.


Selected publications

Walker AS, White IR, Turner RM, Yang HL, Wen YT, White NJ, Sharland M*, Thwaites GE.* Personalised randomised controlled trial designs – a new paradigm to define optimal treatments for carbapenem-resistant infections. Lancet Inf Dis 2021;21(6):e175-e181.

Maitland K*, Kiguli S*, Olupot-Olupot P*, Engoru C, Mallewa M, Saramago Goncalves P, Opoka RO, Mpoya A, Aloroker F, Nteziyaremye J, Chagaluka G, Kennedy N, Namanyanga C, Nakuya M, Uyoga S, Byabazaire DK, M’baya B, Wabwire B, Frost G, Bates I, Evans JA, Williams TN, George EC*, Gibb DM*, Walker AS* for the TRACT trial group. Immediate transfusion in African children with uncomplicated severe anemia. N Engl J Med 2019;381(5):407-419. *contributed equally.

Maitland K*, Olupot-Olupot P*, Kiguli S*, Chagaluka G, Aloroker F, Opoka RO, Mpoya A, Engoru C, Nteziyaremye J, Mallewa M, Kennedy N, Nakuya M, Namanyanga C, Kayaga J, Uyoga S, Byabazaire DK, M’baya B, Wabwire B, Frost G, Bates I, Evans JA, Williams TN, Saramago Goncalves P, George EC*, Gibb DM*, Walker AS* for the TRACT trial group. Transfusion volume for children with severe anemia in Africa. N Eng J Med 2019;381(5):420-431.

Thwaites GE, Scarborough M, Szubert A, Nsutebu E, Tilley R, Greig J, Wyllie SA, Wilson P,  Auckland C, Cairns J, Ward D, Lal P, Guleri A, Jenkins N, Sutton J, Wiselka M, Armando GR, Graham C, Chadwick PR, Barlow G, Gordon NC, Young B, Meisner S, McWhinney P, Price DA, Harvey D, Nayar D, Jeyaratnam D, Planche T, Minton J, Hudson F, Hopkins S, Williams J, Török ME, Llewelyn M, Edgeworth JD, Walker AS on behalf of the United Kingdom Clinical Infection Research Group (UKCIRG). Adjunctive rifampicin for Staphylococcus aureus bacteraemia (ARREST): a multicentre, randomised, double-blind, placebo-controlled trial. Lancet 2018; 391(10121):668-678.

HWalker AS*, Mason A*, Quan TP, Fawcett N, Watkinson P, Llewelyn M, Stoesser N, Finney J, Davies J, Wyllie DH, Crook DW, Peto TEA. Mortality risks associated with emergency admissions during weekends and public holidays: an analysis of electronic health records. Lancet 2017;390(10089);62-72.

Akim J, Musiime V, Szubert AJ, Mallewa J, Siika A, Agutu C, Walker S, Pett SL, Bwakura-Dangarembizi M, Lugemwa A, Kaunda S, Karoney M, Musoro G, Kabahenda S, Nathoo K, Maitland K, Griffiths A, Thomason MJ, Kityo C, Mugyenyi P, Prendergast AJ*, Walker AS*, Gibb DM* on behalf of the REALITY trial team. Enhanced prophylaxis plus antiretroviral therapy for advanced HIV infection in Africa. N Eng J Med 2017;377:233-245.

Mead S, Burnell M, Lowe J, Thompson A, Lukic A, Porter MC, Carswell C, Kaski D, Kenny J, TzeHow M, Bjurstrom N, Gorham M, Druyeh R, Wadsworth J, Jaunmuktane Z, Brandner S, Hyare H, Rudge R, Walker AS*, Collinge J*. Clinical trial simulations based on genetic stratification and the natural history of a functional outcome measure in Creutzfeldt-Jakob disease. JAMA Neurology 2016;73(4):447-55.

Bwakura-Dangarembizi M, Kendall L, Bakeera-Kitaka S, Nahirya-Ntege P, Keishanyu R, Nathoo K, Spyer MJ, Kekitiinwa A, Lutaakome J, Mhute T, Kasirye P, Munderi P, Musiime V, Gibb DM*, Walker AS*, Prendergast AJ* and the ARROW Trial Team. A randomized trial of prolonged cotrimoxazole in HIV-infected children in Africa. N Engl J Med 2014; 370: 41-53.

Paton NI, Kityo C, Hoppe A, Reid A, Kambugu A, Lugemwa A, van Oosterhout J, Kiconco M, Siika A, Mwebaze R, Abwola M, Abongomera G, Mweemba A, Alima H, Atwongyeire D, Nyirenda R, Boles J, Thompson J, Tumukunde D, Chidziva E, Mambule I, Arribas JR, Easterbrook PJ, Hakim J, Walker AS*, Mugyenyi P* for the EARNEST Trial Team. Assessment of second-line antiretroviral regimens for HIV therapy in Africa. N Eng J Med 2014;371(3):234-47.

Eyre DW, Cule ML, Wilson DJ, Griffiths D, Vaughan A, O'Connor L, Ip CLC, Golubchik T, Batty EM, Didelot X, Piazza P, Bowden R, Dingle KE, Harding RM, Crook DW, Wilcox MH*, Peto TEA*, Walker AS*. Diverse sources of C. difficile infection identified on whole genome sequencing. N Eng J Med 2013;369(13):1195-205. doi: 10.1056/NEJMoa1216064.

ARROW Trial Team. ARROW: a 5-year randomised factorial trial of routine versus clinically driven laboratory monitoring and first-line antiretroviral therapy strategies in HIV-infected African children. Lancet 2013; 381(9875):1391-403. doi: 10.1016/S0140-6736(12)62198-9.

Walker AS, Ford D, Gilks C, Munderi P, Ssali F, Reid A, Katabira E, Grosskurth H, Mugyenyi P, Hakim J, Darbyshire JH, Gibb DM, Babiker AG. Daily co-trimoxazole prophylaxis in severely immunosuppressed HIV-infected adults in Africa started on combination antiretroviral therapy: an observational analysis of the DART cohort. Lancet 2010;375:1278-86.





Research Interests

  • HIV
  • Hepatitis C
  • Serious bacterial infections
  • Design of randomised trials and observational studies


Research Areas