In episode 5, we explore trial design and measurement with an example of an intervention to reduce alcohol consumption by reducing the strength of alcohol. Dr Emma Davies interviews Dr Parvati Perman-Howe about her PhD study, which involved a double-blind randomised controlled cross-over pilot trial. Dr Perman-Howe discusses the purpose of a pilot trial, the design of the study, and some of the things she learnt from the process, as well as sharing some tips and advice.