Table 1 Aims and research methods of the QRI protocol [14] and aspects included in the QRI-Two

i) Interviews with RCT staff (investigators and front-line recruiters); sometimes patients

To explore key aspects of RCT design and recruitment pathway, views about interventions, intentions in relation to recruitment.

Qualitative thematic analysis

ii) Mapping a patient’s pathway through screening, eligibility, and randomisation, using screening logs and flow charts; accrual data

To identify patterns in screening and eligibility assessment and accrual data, for example differences in numbers screened, eligible, approached, and randomised in sites

Qualitative content analysis and simple quantification

iii) Audio-recordings of recruitment appointments where the RCT is presented by recruiters to eligible patients

To assess clarity of study presentation by recruiters (compared with intentions in interviews) and reactions of patients to study terminology

Qualitative thematic and conversation analysis

iv) Scrutiny of study documents, e.g. RCT protocol, patient information/consent forms, study website^a

To understand RCT design, purpose, evidence base, inclusion/exclusion criteria, recruitment pathway, and interventions in protocol, and clarity and consistency with patient information.

Documentary content analysis

QRI phase II

a) Present phase I findings to the CI/RCT team^b

b) Develop the plan of actions to optimise recruitment, and implement jointly with RCT team