John's main field of interest is the design and analysis of clinical trials, particularly those in cardiovascular disease.
John has a particular interest in demystifying statistical methods and assessing their value and best use in trials in cardiology. Major current topics of research include: the win ratio approach to a hierarchical composite of outcomes with clinical priorities, the value of repeat-event versus time-to-first event analyses, the use of covariate adjustment in clinical trials, and how best to handle competing risks.
Outside of methodological work, he provides expert statistical advice on a number of trials in cardiology and is the statistical member of several trial data monitoring committees.