Dr Lydia Emerson

I am a trials methodologist specialising in the design and delivery of process evaluations embedded within complex intervention trials. My research examines how context and quality of intervention delivery influence implementation, mechanisms of action, and outcomes. I develop methods that help trial teams anticipate delivery challenges and interpret intervention effectiveness with greater confidence.

I completed my PhD at Queen’s University Belfast through a nationally competitive four-year Medical Research Council Trials Methodology Research Fellowship. During the fellowship, I conceived and developed POETIC (PrOcess Evaluation of Trials In Critical care), a structured framework for designing and conducting process evaluations in critical care trials. POETIC has been used in at least nine, mainly NIHR-funded trials and is developing into a broader programme of empirical, operational, and prospective process evaluation methodology.

I have led process evaluations within major multicentre trials, including VAPrapid-2, POPPI, A2B, and SINFONIA, and contributed methodological expertise to SANDWICH and SHORTER. I also designed and led a mixed-methods consent study within a trial (SWAT) embedded in the ABC post-ICU transfusion trial. Together, these studies span adult and paediatric critical care, perioperative and anaesthesia research, post-ICU recovery, and complex behavioural and service-level interventions.

At Exeter, my principal role is as Senior Research Fellow for the process evaluation of the NIHR-funded CHART trial (CompreHensive geriatric Assessment for oldeR people with hearT failure and frailty). This work extends my research into heart failure, frailty, and integrated health-services research. I am also process evaluation lead and co-investigator on two major NIHR HTA-funded trials in adult and paediatric critical care.

My aim is to ensure that process evaluation is an active component of trial methodology: informing intervention design, identifying delivery risks prospectively, and generating evidence that is more interpretable, implementable, and useful to clinical practice.