Trials Within Trials? Researcher, Funder and Ethical Perspectives on the Practicality and Acceptability of Nesting Trials of Recruitment Methods in Existing Primary Care Trials

Abstract

Trials frequently encounter difficulties in recruitment, but evidence on effective recruitment methods in primary care is sparse. A robust test of recruitment methods involves comparing alternative methods using a randomized trial, 'nested' in an ongoing 'host' trial. There are potential scientific, logistical and ethical obstacles to such studies.