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Professor Tess Harris

Professor of Primary Care Research
Primary care database research, primary care health promotion research and teaching

My research focuses on using routine primary care databases to answer important questions about health, health service use and health outcomes and also on health promotion in primary care, particularly through trials.

The primary care epidemiology work uses large primary care databases eg Clinical Practice Research Database with linkages to mortality, Hospital Episode Statistics and deprivation data for innovative studies including in the areas of diabetes and infections, polypharmacy, learning disability, bereavement and excess mortality during the COVID-19 pandemic. Current active grants include: diabetes and infections (incorporating importance of glycaemic control and variability) awarded by NIHR; tuberculosis and non-communicable disease risk, awarded by US National Institute of Health, in collaboration with Emory University, US; and epidemiology of neuromuscular disease awarded by Muscular Dystrophy UK.

The health promotion trials include walking interventions in adults and older adults funded by NIHR (PACE-Lift, PACE-UP), which demonstrated long-term increases in objectively measured physical activity and reductions in fractures and cardiovascular outcomes, as well as current NIHR funded trials using physical activity to reduce smoking (TARS) and helping pregnant women who quit smoking to remain smoke free post-partum (BabyBreathe).

My teaching portfolio includes being module lead for the MBBS T-year clinical epidemiology Case Analysis Project, clinical assessment of medical students in all years of MBBS, contributing to immunisations and population health teaching and to the iBSc primary care module. I also provide PhD and primary care academic clinical fellow supervision.

Additionally, I maintain a clinical role and work as a part-time salaried GP in Oxfordshire.







Tess Harris is a Professor of Primary Care Research in the Population Health Research Institute at St George's, University of London and a member of the Primary Care Epidemiology Group within the research institute. She specialises in primary care database research and also in health promotion research in primary care, particularly trials.

Her MD, awarded in 2005, examined depression, disability and use of primary care services by older people and linked survey and routine general practice data. She has been at St George's since 1994, when she was appointed as a lecturer. Prior to this, Dr Harris graduated in Medicine from St George's in 1988, completed her vocational training in General Practice, and gained her Membership of the Royal College of General Practitioners with distinction in 1992. Following this she worked in India for a year, training village health workers and working on a primary health care programme. In 1994 Dr Harris gained an MSc in Epidemiology from the London School of Hygiene and Tropical Medicine with a distinction.

She works part time as a GP at Sonning Common Health Centre in Oxfordshire, alongside her academic work at St George's, University of London, and has edited a book on managing older people in primary care. Professor Harris currently sits on five Programme grant / Trial Steering Committees for the National Institute for Health Research. 


Tess Harris is a Professor of Primary Care Research in the Population Health Research Institute. Her research focuses on the use of primary care databases to answer important questions about health service use and health outcomes and on health promotion, particularly trials conducted in primary care.

The primary care database work is in collaboration with other Primary Care Epidemiology Group members and is currently focusing on the following areas: diabetes and infections (NIHR Research for Patient Benefit); medicines optimisation in patients with multi-morbidity; Tuberculosis and non-communicable diseases (National Institute for Health, US); excess mortality during COVID-19 pandemic; and epidemiology of neuromuscular disorders (Muscular Dystrophy UK). Other recently published work has examined healthcare use and health outcomes for patients with learning disability (Health Services and Delivery Research, NIHR), quality of care for care home patients (BUPA foundation) and health outcomes following partner bereavement (Dunhill Trust).

In terms of health promotion work, current research focuses on multi-centred trials of smoking cessation where she is a co-investigator and the London trial site co-lead, including the BabyBreathe trial of a complex intervention to prevent return to smoking post-partum (NIHR Public Health Research Programme) and the TARS trial of a physical activity intervention to reduce smoking (NIHR Health Technology Assessment Programme).

Professor Harris has also recently been chief investigator for two large primary care randomised controlled trials of pedometer-based walking interventions, both providing objective physical activity outcome measures and novel long-term follow-up data. These are:

• PACE-Lift: (Pedometer Accelerometer Consultation Evaluation-Lift). A randomised controlled trial of a complex walking intervention in 60-75 year olds, funded by Research for Patient Benefit, NIHR May 2011-January 2014. It showed significant increases in both step-counts and time in moderate-to-vigorous physical activity for the intervention group compared to controls, sustained at one year. Four-year follow up was undertaken from October 2015-October 2016 and also showed persistent trial effects.

PACE-UP: (Pedometer And Consultation Evaluation –UP). A randomised controlled trial of a pedometer-based walking intervention with and without practice nurse support in 45-75 year olds, funded by the Health Technology Assessment Programme, NIHR March 2012-May 2017. Initial trial results at one year showed favourable effects of both nurse and postal interventions compared to controls in terms of both step counts and time in moderate-to-vigorous physical activity. Further funding for three-year follow up was awarded and showed persistent effects of the intervention on physical activity levels. Recent work combining the trials and examining long-term health outcomes using data from primary care records showed that the interventions significantly reduced the rate of cardiovascular events and fractures at 4 year follow-up.  Both trials have been included in recent systematic reviews and meta-analyses of long-term physical activity interventions and also step-count interventions.





to see all my publications please see my ORCID profile

Recent Publications 2021-2023

  1. Carey I, Critchley J, Chaudhry Um, DeWilde S, Cook D, Limb E, Harris T. Exploring ethnic variations in the risk of infections in people with prediabetes and type 2 diabetes: a matched cohort study. March 2023 Diabetes Care 2023; 46(6):1-9 
  2. Vetrovsky T, Kral N, Pfeiferova M, Kuhnova J, Novak J, Wahlich C, Jaklova A, Jurkova K, janek M, Omcirk D, Capek V, Maes I, Steffl M, Ussher M, Tufano J, Elavsky S, vanDyck D, Cimler R, Yates T, Harris T, Seifert B. mHealth intervention delivered in general practice to increase physical activity and reduce sedentary behaviour of patients with prediabetes and type 2 diabetes (ENERGISED): rationale and study protocol for a pragmatic randomised controlled trial. BMC Public Health 23; 613 (2023)
  3. Chattopadhyay K, Mishra P, Singh K, Singh K, Harris T, Hamer M, Greenfield S, Manjunath N, Nair Rm Mukherjee S, Tandon N, Lewis S, Kinra S, Prabhakaran D. Yoga Programme for Type 2 Diabetes Prevention (YOGA-DP) among high risk people in India: A Multicenter Feasibility Randomized Controlled Trial. Diabetes Ther 2023:
  4. Taylor A, Thompson T, Streeter A, Chynoweth J, Snowsill T, Ingram W, Ussher M, Aveyard P, Murray R, Harris T et al. Effectiveness & cost-effectiveness of behavioural support for prolonged abstinence in smokers wishing to reduce but not quit: randomised controlled trial of physical activity assisted reduction of smoking (TARS). Addiction 2023:
  5. Ibison J, Chaudhry U, Driscoll J, Harris T. Helping medical undergraduate students to understand healthcare costs. Medical Education 2023:
  6. Carey I, Nirmalanathan N, Harris T, DeWilde S, Chaudhry U, Limb E, Cook, D. Prevalence of co-morbidity & history of recent infection in patients with neuromuscular disorders: a cross-sectional analysis of UK primary care data. PLOS one. 2023.
  7. Vetrovsky T, Borowiec A, Jurik R, Smigielski W, Steffl M, Tufano J, Drygas W, Stastny P, Harris T, Wahlich C, Malek L. Do physical activity interventions combining self-monitoring with other strategies provide an additional benefit compared to self-monitoring alone? A systematic review and meta-analysis.. Br J Sports Med 2022; 0:1–12. doi:10.1136/bjsports-2021-105198
  8. Mishra P, Harris T, Greenfield S, Hamer M, Lewis S, Singh K, Nair R, Mukherjee S, Manjunath N, Tandon N, Kinra S, Prabhakaran D, Chattopadhyay K. Feasibility Trial of Yoga Programme for Type 2 Diabetes Prevention (YOGA-DP) among High-Risk People in India: A Qualitative Study to Explore Participants’ Trial- and Intervention-Related Barriers and Facilitators. J. Environ.Res. Public Health 2022, 19, 5514.
  9. Ahmad S, Carey IM, Harris T, Cook DG, DeWilde S, Strachan D. The rising tide of dementia deaths? Triangulation of data from 2000-2015 for death certification, primary care and hospital record data. BMC Geriatrics 2021; 21:375
  10. Czwikla G, Boen F, Cook D, de Jong J, Harris T, Hilz L et al. Equity-specific effects of interventions to promote physical activity among middle-aged and older adults: Results from applying a novel equity-specific re-analysis strategy. Int J Behav Nutr &Phys Act. 2021;18:65
  11. Carey I, Cook D, Harris T, DeWilde S, Chaudhry U, Strachan D. Risk factors for excess all-cause mortality during the first wave of the COVID-19 pandemic phase in England: a retrospective cohort study of primary care data. PLOS ONE 2021;
  12. Carey I, Bancroft E, Nirmalananthan N, Harris T, DeWilde S, Chaudhry U, Cook D. Prevalence and incidence of recorded neuromuscular conditions in the UK between 2000 and 2019: A retrospective study using primary care data. PLOS ONE 2021;
  13. Mishra P, Greenfield S, Harris T Hamer M, Lewis S et al. Title: Yoga programme for type-2 diabetes prevention (YOGA-DP) among high-risk people: a qualitative study to explore reasons for non-participation in a feasibility randomised controlled trial in India. Front. Public Health 2021

Current Research as Principal Investigator:

2021-2023: People living with diabetes and intermediate hyperglycaemia: risk of infections and effects of average level and variability of glycated haemoglobin (HbA1C) on this risk, in people of different ethnic origin. Funding agency: Research for Patient Benefit (NIHR). Principal Investigators: Harris T & Critchley J, Co-Investigators: Carey I, DeWilde S, Cook D. Start and end dates Dec 2021-Sept 2023. Total award: £153K.

Current Research Grants As Co-Investigator:

2023-2027: HEAL-D (Healthy Eating & Active Lifestyles for Diabetes): a multicentre, pragmatic randomised controlled trial comparing effectiveness and cost-effectiveness of culturally tailored versus standard diabetes self-management programmes in Black-African and Black-Caribbean adults with type 2 diabetes. Funding agency: NIHR Health Technology Assessment Programme NIHR151372. Principal Investigators: Louise Goff (Leicester University) & Barbara McGowan (Guy's & St Thomas, London). Co-investigators: Clare Robinson, Tess Harris, Michael Ussher, Mark Ashworth, Jeremy Dale, Andrew Healey, Huajie Jin, Peter Bower, Carol Rivas, Jane Thorpe, Eleanor Hoverd, Sandra Tomlinson, Tony Kelly. Start and end dates: Aug 2023-July 2027.Total award: £2.3M

2021-2023: The role of tuberculosis Disease on Non-Communicable Disease Risk: Comparative Analysis of Large healthcare Databases. Funding agency: National Institute of Health (NIH) US. Principal Investigators: Critchley J & Magee M. Co-Investigators: Carey I, Phillips L, Rhee M, Harris T, DeWilde S, Cook D. Start and end dates: Oct 2021-Mar 2023. Total award: $372K.

2020-2024: BabyBreathe Trial (A RCT of a complex intervention to prevent return to smoking postpartum). Funding agency: Public Health Research Programme, NIHR. Principal Investigator: Notley C. Co-Investigators: Bauld L, Ussher M, Harris T, Holland R, Naughton F, Hardeman W, Smith D, Clarke A, Turner D, Duneclift S, Gilroy V. Start and end dates: Oct 2020-Feb 2024. Total award: £1.5M.

Recent Research Grants:

2019-2022: Temporal and regional trends in neuromuscular disease prevalence and incidence, and the health and healthcare of people with neuromuscular conditions in the UK between 2000-2018. Funding agency: Muscular Dystrophy UK. Principal Investigator: Carey I. Co-Investigators: Harris T, DeWilde S, Cook D, Nirmalananthan N. Start & end dates: Dec 2019- Aug 2022. Total award: £114K.

2017-2020: TARS trial: A multi-centred trial of physical activity assisted reduction of smoking. Funding agency: HTA Programme (NIHR). Principal Investigator: Taylor A. (Plymouth). Co-Investigators: Creanor S, Green C, Greaves, C, Ussher, M, Harris T, Aveyard, P. Start and end dates: May 2017-Sept 2020. Total award: £1.8M.

2018-2020: Yoga programme for type-2 diabetes prevention (YOGA-DP) among high risk people in India: intervention development and feasibility study. Funding agency: MRC NUHR DfID Welcome Trust Global Health Trials. (MR/R018278/1). Principal Investigator: Chattopadhyay K (Nottingham). Co-Investigators: Kinra S, Lewis S, Hamer M, Greenfield S, Harris T, Manjunath N, Tandon N, Prabhakaran D, Harper D. Start and end dates: May 2018-April 2020. Total Award: £127K.

2014-2019: NIHR General Practice In Practice Fellowship award:(Dr Shaleen Ahmad) (extended for 2 maternity leaves). Supervisor Harris T. Total award: £78k

2012-2017: PACE-UP trial: (Pedometer And Consultation Evaluation–UP). RCT of a pedometer-based walking intervention with and without practice nurse support in primary care patients aged 45-74 years.  Funding agency: Health Technology Assessment Programme (NIHR). Principal Investigator: Harris T. Co-investigators: Cook DG, Kerry SM, Victor CR, Shah S, Iliffe S, Ekelund U, Whincup P, Ussher M, Fox-Rushby J. Start & end dates: Mar 2012-May 2017. Total award: £1.3M.(including additional £171k for 3 year follow-up awarded 2015).

2011-2014: PACE-Lift: (Pedometer Accelerometer Consultation Evaluation-Lift). A randomised controlled trial of a complex intervention by primary care nurses to increase walking in patients aged 60-75 years. Funding agency: Research for Patient Benefit (NIHR). Principal Investigator: Harris T. Co-investigators: Cook DG, Kerry SM, Victor CR, Iliffe S, Ekelund U, Whincup PW, Woodcock A, Beighton C. Start & end dates: May 2011-Jan 2014. Award: £277K

2013-2016: An Evaluation of the Effectiveness of Annual Health Checks and Quality of Health Care for Adults with Learning Disability. Funding agency: Health Service Delivery Research (NIHR). Principal investigator: initially Shah S, now Carey I. (SGUL). Co-investigators Harris T, DeWilde S, Cook D. Start & end dates: Feb 2013-Oct 2016. Total award: £311k.

2011- 2013: Bereavement Study. The health and healthcare impact of bereavement in older people. Funding agency: Dunhill  Medical Trust. PI: Shah S (SGUL), Co-investigators: Carey I, Harris T, DeWilde S, Victor C, Cook D. Start & end dates:  Apr2011-Sep 2013. Award: £132K.

2009-2011: Care Home Study. An investigation of the quality of primary care for older care home residents using linkage within a primary care database. Funding agency: BUPA Foundation. PI: Shah S (SGUL). Co-Ix: Carey I, Harris T, DeWilde S, Hubbard R, Lewis S, Cook D. Feb 2009-April 2011. Award: £144K.


Internal collaborations

Professor Derek Cook, Dr Iain Carey, Dr Stephen DeWilde, Professor Peter Whincup, Professor Michael Ussher, Professor Julia Critchley, Dr Umar Chaudhry, Dr Charlotte Wahlich, Dr Niranjanan Nirmalananthan Professor Emma Baker.

External collaborations

Professor Caitlin Notley, (University of East Anglia)

Professor Matthew Magee, Rollins School of Public Health, Emory University, US

Professor Adrian Taylor (Plymouth University Peninsula Schools of Medicine and Dentistry, UK)

Professor Christina Victor (Brunel, UK)
Professor Steve Iliffe (University College London, UK)
Professor Ulf Ekelund (School of Sports Science, Oslo, Norway)
Professor Julia Fox-Rushby (King's College, UK)

Dr Tomas Vetrovsky, (Faculty of Physical Education and Sport, Charles University, Prague, Czech Republic)

Dr Lee David (10 Minute CBT, UK)

 Dr Kaushik Chattopadhyay, (University of Nottingham)


I am currently module lead for the clinical epidemiology Case Analysis Project in T-year of MBBS.

I examine in clinical OSCEs for all years of MBBS. I teach about population health and critical appraisal on the Primary Care iBSc and about clinical and public health aspects of immunisation in the Life Protection modules for MBBS4 and MBBS5.


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