Mark Joy

Dr Mark Joy

Senior Lecturer in Data Modelling and Population Health
+44 (0)1483 689932



After studying pure Mathematics to post-graduate level at Warwick, Mark taught as a secondary teacher in London for 5 years. He then re-trained in Information Systems Engineering and began research in Neural Networks; specifically, studying mathematically the stability of nonlinear circuits of Hopfield-type as a system of nonlinear ordinary differential equations. He also began lecturing Mathematics and Statistics at Kingston University, London.

Mark became interested in the Statistics in HealthCare and began studying predictive models for Occupancy at the hospital-level and also classical statistical and other predictive models for HSMRs (and other risks) in secondary healthcare.

Mark has extensive Commercial experience with big data sets in HealthCare, nationally and internationally, working as a Senior Statistician at Dr Foster (one of the leading providers of healthcare variation analysis and clinical benchmarking solutions worldwide). For the last four years he has been Statistician with the Global Comparators project, a major international hospital network created in 2011 to be a global hospital benchmarking collaborative.

Research interests

Nonlinear Differential EquationsNeural NetworksMulti-Level Statistical Models in MedicinePredictive Modelling of HealthCare Systems


Hajira Dambha-Miller, William Hinton, Christopher R Wilcox, Agnieszka Lemanska, Mark Joy, Michael Feher, Beth Stuart, Simon de Lusignan, Julia Hippisley-Cox, Simon Griffin (2023)Mortality from angiotensin-converting enzyme-inhibitors and angiotensin receptor blockers in people infected with COVID-19: a cohort study of 3.7 million people, In: Family Practice40(2)pp. 330-337 Oxford University Press

Concerns have been raised that angiotensin-converting enzyme-inhibitors (ACE-I) and angiotensin receptor blockers (ARBs) might facilitate transmission of severe acute respiratory syndrome coronavirus 2 leading to more severe coronavirus disease (COVID-19) disease and an increased risk of mortality. We aimed to investigate the association between ACE-I/ARB treatment and risk of death amongst people with COVID-19 in the first 6 months of the pandemic. We identified a cohort of adults diagnosed with either confirmed or probable COVID-19 (from 1 January to 21 June 2020) using computerized medical records from the Oxford-Royal College of General Practitioners (RCGP) Research and Surveillance Centre (RSC) primary care database. This comprised 465 general practices in England, United Kingdom with a nationally representative population of 3.7 million people. We constructed mixed-effects logistic regression models to quantify the association between ACE-I/ARBs and all-cause mortality among people with COVID-19, adjusted for sociodemographic factors, comorbidities, concurrent medication, smoking status, practice clustering, and household number. There were 9,586 COVID-19 cases in the sample and 1,463 (15.3%) died during the study period between 1 January 2020 and 21 June 2020. In adjusted analysis ACE-I and ARBs were not associated with all-cause mortality (adjusted odds ratio [OR] 1.02, 95% confidence interval [CI] 0.85-1.21 and OR 0.84, 95% CI 0.67-1.07, respectively). Use of ACE-I/ARB, which are commonly used drugs, did not alter the odds of all-cause mortality amongst people diagnosed with COVID-19. Our findings should inform patient and prescriber decisions concerning continued use of these medications during the pandemic.

M. Lee, Mark Joy (2020)Outcomes of obstructed abdominal wall hernia: results from theUKnational small bowel obstruction audit, In: BJS open4(5)pp. 924-934 Oxford Univ Press

Background Abdominal wall hernia is a common surgical condition. Patients may present in an emergency with bowel obstruction, incarceration or strangulation. Small bowel obstruction (SBO) is a serious surgical condition associated with significant morbidity. The aim of this study was to describe current management and outcomes of patients with obstructed hernia in the UK as identified in the National Audit of Small Bowel Obstruction (NASBO). Methods NASBO collated data on adults treated for SBO at 131 UK hospitals between January and March 2017. Those with obstruction due to abdominal wall hernia were included in this study. Demographics, co-morbidity, imaging, operative treatment, and in-hospital outcomes were recorded. Modelling for factors associated with mortality and complications was undertaken using Cox proportional hazards and multivariable regression modelling. Results NASBO included 2341 patients, of whom 415 (17 center dot 7 per cent) had SBO due to hernia. Surgery was performed in 312 (75 center dot 2 per cent) of the 415 patients; small bowel resection was required in 198 (63 center dot 5 per cent) of these operations. Non-operative management was reported in 35 (54 per cent) of 65 patients with a parastomal hernia and in 34 (32 center dot 1 per cent) of 106 patients with an incisional hernia. The in-hospital mortality rate was 9 center dot 4 per cent (39 of 415), and was highest in patients with a groin hernia (11 center dot 1 per cent, 17 of 153). Complications were common, including lower respiratory tract infection in 16 center dot 3 per cent of patients with a groin hernia. Increased age was associated with an increased risk of death (hazard ratio 1 center dot 05, 95 per cent c.i. 1 center dot 01 to 1 center dot 10;P = 0 center dot 009) and complications (odds ratio 1 center dot 05, 95 per cent c.i. 1 center dot 02 to 1 center dot 09;P = 0 center dot 001). Conclusion NASBO has highlighted poor outcomes for patients with SBO due to hernia, highlighting the need for quality improvement initiatives in this group.

Mark Joy, John Williams, Subo Emanuel, Debasish Kar, Xuejuan Fan, Gayathri Delanerolle, Benjamin CT Field, Christian Heiss, Kevin G Pollock, Belinda Sandler, Jasleen Arora, James P Sheppard, Michael D. Feher, F. D. Richard Hobbs, Simon De Lusignan (2022)Trends in direct oral anticoagulant (DOAC) prescribing in English primary care (2014- 2019), In: Heart

Background: In England, most prescribing of direct-acting oral anticoagulants for atrial fibrillation (AF) is in primary care. However, there remain gaps in our understanding of dosage and disparities in use. We aimed to describe trends in direct oral anticoagulant (DOAC) prescribing, including dose reduction in people with renal impairment and other criteria, and adherence. Methods: Using English primary care sentinel network data from 2014 to 2019, we assessed appropriate DOAC dose adjustment with creatinine clearance (CrCl). Our primary care sentinel cohort was a subset of 722 general practices, with 6.46 million currently registered patients at the time of this study. Results: Of 6 464 129 people in the cohort, 2.3% were aged ≥18 years with a diagnosis of AF, and 30.8% of these were prescribed vitamin K antagonist and 69.1% DOACs. Appropriate DOAC prescribing following CrCl measures improved between 2014 and 2019; dabigatran from 21.3% (95% CI 15.1% to 28.8%) to 48.7% (95% CI 45.0% to 52.4%); rivaroxaban from 22.1% (95% CI 16.7% to 28.4%) to 49.9% (95% CI 48.5% to 53.3%); edoxaban from 10.0% (95% CI 0.3% to 44.5%) in 2016 to 57.6% (95% CI 54.5% to 60.7%) in 2019; apixaban from 30.8% (95% CI 9.1% to 61.4%) in 2015 to 60.5% (95% CI 57.8% to 63.2%) in 2019. Adherence was highest for factor Xa inhibitors, increasing from 50.1% (95% CI 47.7% to 52.4%) in 2014 to 57.8% (95% CI 57.4% to 58.2%) in 2019. Asian and black/mixed ethnicity was associated with non-adherence (OR 1.81, 95% CI 1.56 to 2.09) as was male gender (OR 1.19, 95% CI 1.15 to 1.22), higher socioeconomic status (OR 1.60, 95% CI 1.52 to 1.68), being an ex-smoker (OR 1.12, 95% CI 1.06 to 1.19) and hypertension (OR 1.07, 95% CI 1.03 to 1.17). Conclusions: The volume and quality of DOAC prescribing has increased yearly. Future interventions to augment quality of anticoagulant management should target disparities in adherence.