The identification of "generic", protocol-specific and organisational barriers to recruitment will facilitate the identification of clinically and locally relevant strategies to address these issues prior to the larger definitive study. Using both the existing literature and the unique insights provided by this study, we will also develop and refine a screening tool of research barriers which will (a) be used to audit recruitment in the larger definitive study and (b) form the basis of a tool relevant for critical care research per se.