My research combines methodological research interests with the conduct of collaborative research studies. Over the past twenty years a large component of this research has been in neurology, with a particular focus on Dementia, Huntington’s Disease (HD) and Multiple Sclerosis (MS). This work includes involvement with the design, conduct and statistical analysis of randomised controlled clinical trials, including a phase II trial in secondary progressive MS (MS-STAT) that provided statistically significant evidence that statins slow both the rate of whole-brain atrophy and the clinical progression of the disease. A large phase III trial of statins in secondary progressive MS (MS-STAT2), funded by the NIHR, is currently in progress.

From a methodological standpoint I have a particular interest in clinical trial design, addressing questions such as quantifying the advantages of extending follow-up, introducing interim visits and introducing novel design features such as run-in periods into trials in neurology. Also, in 2021 Sir Nicholas Wald and I showed that claims that that there is no safe level of alcohol consumption (made on the basis of a genetic analysis of a large Chinese cohort study) were unsound due to a methodological flaw in the analysis that had been performed. 

I also collaborate with colleagues at the Department of Psychiatry at Oxford University, on a program of research involving the conduct and analysis of randomised trials and cohort studies. One such study is the HOME study, an NIHR funded randomised controlled trial investigating whether a programme of Proactive Psychological Medicine can reduce the time older people admitted to hospital spend there. Results from this trial are about to be published.

My research is not limited to the UK. I have been involved in the design and analysis of randomised controlled trials endeavouring to reduce childhood mortality in India (CHAMPION) and Guinea-Bissau (EPICS), and randomised controlled trials in India (STRIPES) and The Gambia (SCORE) that demonstrated the effectiveness of additional schooling on educational attainment (STRIPES) in primary school age children. Follow-up trials in India (CHAMPION2/STRIPES2) continue this work. 

In the past I have worked on major randomised controlled trials and epidemiological studies in many disease areas, including asthma and breast cancer. I have also carried out methodological work on estimating and adjusting for the effect of measurement error in cohort studies where exposure over a lifetime is related to disease risk.