Dr Thomas Cowling


Assistant Professor
in Clinical Epidemiology

Keppel Street
United Kingdom

I am an Assistant Professor in the Department of Non-communicable Disease Epidemiology, Faculty of Epidemiology and Population Health.

My current role is based in the Electronic Health Records (EHR) Research Group which I joined in November 2021. I work on COVID-19 projects as part of the OpenSAFELY collaboration with the Bennett Institute at the University of Oxford (see 'Research' below).

Before this, I was based in the Department of Health Services Research and Policy and completed a Medical Research Council (MRC) Skills Development Fellowship (2018-2021). This Fellowship focused on measures of patient morbidity and the prognosis of cancer patients, using national cancer and hospital data. I also worked on national NHS audits for colorectal and prostate cancer, in collaboration with the Royal College of Surgeons.

I joined LSHTM in 2017 from Imperial College London where I completed degrees in Biomedical Sciences (BSc), Public Health (MPH), and Health Services Research (PhD). My PhD investigated access to general practice services nationally and was funded by a National Institute for Health Research (NIHR) Doctoral Research Fellowship.


Faculty of Epidemiology and Population Health
Department of Non-communicable Disease Epidemiology


Centre for Global Chronic Conditions
Centre for Statistical Methodology


MSc Health Data Science: I am part of the Programme Committee that leads this MSc. I am also a Module Organiser for the ‘Data Challenge’ module, a personal tutor, and a project supervisor.

MSc Public Health: I have taught on the Health Care Evaluation, Health Services, and Principles and Practice of Public Health modules of this MSc.

I currently supervise two PhD students:

  • Jemma Boyle - Using national routine data to explore the utilisation and outcomes of multimodal treatment in the management of colorectal cancer
  • Caroline Chesang - Estimating treatment effects using real world data when there are competing risks: applications to causes of death of prostate cancer patients

I have supervised two completed PhDs:

  • Matthew Parry (2021) - Use of routinely collected hospital data to explore access to and outcomes from different radiotherapy treatment strategies for locally advanced prostate cancer
  • David Wallace (2021) - Liver transplantation as treatment for hepatocellular carcinoma: a national study using linked electronic healthcare records

Current and prospective students are very welcome to contact me.


My research currently focuses on the epidemiology of COVID-19.

Working as part of the OpenSAFELY collaboration, I am examining which characteristics of individuals are associated with the symptoms experienced (if any) after a SARS-CoV-2 infection. This includes sociodemographic characteristics, pre-existing health conditions, host immunity, as well as characteristics of the infection (such as virus gene profile). To do this, I am using data from the Office for National Statistics (ONS) COVID-19 Infection Survey linked to general practice records and COVID-19 testing data.

My main methodological interest is how we should model patient morbidity in electronic healthcare records when large sample sizes are available. Larger samples may allow us to incorporate more information about each patient than is done by conventional methods. My work in this area has, so far, investigated approaches for selecting small sets of diagnosis codes from much larger sets of codes and for modelling many interactions between health conditions using machine learning approaches.

Research Area
Clinical care
Clinical databases
Health care policy
Health inequalities
Health outcomes
Health services research
Statistical methods
Electronic health records

Selected Publications

Logistic regression and machine learning predicted patient mortality from large sets of diagnosis codes comparably.
Cowling TE; Cromwell DA; Bellot A; Sharples LD; van der Meulen J
Journal of Clinical Epidemiology
Determinants of Variation in the Use of Adjuvant Chemotherapy for Stage III Colon Cancer in England.
Boyle JM; Kuryba A; Cowling TE; Aggarwal A; Hill J; van der Meulen J; Walker K; Braun MS
Clinical oncology
One-year mortality of colorectal cancer patients: development and validation of a prediction model using linked national electronic data
Cowling TE; Bellot A; Boyle J; Walker K; Kuryba A; Galbraith S; Aggarwal A; Braun M; Sharples LD; van der Meulen J
Br J Cancer
A novel approach selected small sets of diagnosis codes with high prediction performance in large healthcare datasets.
Cowling TE; Cromwell DA; Sharples LD; van der Meulen J
Journal of Clinical Epidemiology
Patient-Reported Functional Outcomes After Hypofractionated or Conventionally Fractionated Radiation for Prostate Cancer: A National Cohort Study in England.
Nossiter J; Sujenthiran A; Cowling TE; Parry MG; Charman SC; Cathcart P; Clarke NW; Payne H; van der Meulen J; Aggarwal A
Journal of clinical oncology
Assessing the Time-Dependent Impact of Performance Status on Outcomes After Liver Transplantation.
Wallace D; Cowling T; McPhail MJ; Brown SE; Aluvihare V; Suddle A; Auzinger G; Heneghan MA; Rowe IA; Walker K
Hepatology (Baltimore, Md)
Physical multimorbidity, health service use, and catastrophic health expenditure by socioeconomic groups in China: an analysis of population-based panel data.
Zhao Y; Atun R; Oldenburg B; McPake B; Tang S; Mercer SW; Cowling TE; Sum G; Qin VM; Lee JT
The Lancet Global Health
See more Publications