Presentation (CTI)

OBJECTIVES: Target differences are the difference in the outcome of interest that a trial is designed to detect. Target differences can be based on important or realistic differences. There are no agreed methods to directly involve patients and the public in determining target differences. We aimed to conduct a scoping review to identify elicitation methods and assess applied tools to seek opinions from patients or the public on target differences.
METHODS: We conducted a snowballing scoping review. Included studies asked patient or public’s opinions directly about important or realistic treatment differences to inform the design or interpretation of trials (i.e. excluded anchor or distribution-based methods). Abstracts and full texts were screened, and data was extracted by one researcher with an independent check done by a second researcher. Validity, feasibility and patient and public involvement (PPI) were assessed based on self-report.
RESULTS: We identified 61 full texts. From these, around 80% were published after 2010. Opinion seeking tools were applied most in neoplasms (20%) and musculoskeletal diseases (20%). Four categories of elicitation methods were identified: trade-off (69%), direct questioning (20%), educational (7%) and reflective (5%) methods. The most common concept elicited by opinion seeking was the minimally important difference (25%). Around half of the studies reported validity (48%), less than a third assessed feasibility (30%). Less than half of the studies reported PPI (41%).
CONCLUSIONS: We identified elicitation methods to directly involve patients and the public in determining important differences in clinical trials. This is a first step in ensuring important differences are robustly defined, and involve patients or the public, to avoid research waste. Their quality and acceptability, and what works in what context, needs to be assessed.