Table 4.

Characteristics of studies included in the QES

Reference (study, country)	Study aim/objectives	Stage of trial	Sample	Interventions	Data collection and analysis
1. Bill-Axelson et al (2009) [66] (Sweden, Finland, Iceland)	To understand attitudes to the randomisation process among patients and clinicians in the hope of rendering the process more acceptable for these stakeholders in future.	2-8 years following randomisation	Nine patients with early prostate cancer (n = 9, 5 participants and 4 non-participants) and randomising clinicians (n = 5)	Radical prostatectomy/watchful waiting	Semi-structured interviews Content analysis
2. Blazeby et al (2014) [67] (United Kingdom)	To determine the feasibility of a main trial of chemotherapy and surgery vs definitive chemoradiotherapy for localised oesophageal squamous cell carcinoma (SCC).	Pre-trial (Feasibility)	26 paired audio recordings of surgery and oncology appointments and 14 in-depth patient interviews.	Neoadjuvant treatment and surgery/definitive chemoradiotherapy	Audio recordings of surgery and oncology appointments and in-depth patient interviews. Conversation analysis Thematic analysis
3. Hamilton et al (2013) [68] (United Kingdom)	To investigate whether it was feasible to undertake a multicentre, RCT comparing disease-free survival and voice outcomes between laser surgery and radiotherapy and particularly factors affecting recruitment and data collection.	Pre-trial (Feasibility)	Surgeons (n = 3) and recruiters (n = 3)	Endoscopic excision/Radiotherapy	Semi-structured interviews/focus groups/audio recordings of recruitment encounters Content and thematic analysis
4. McSweeney, et al. (2017) [70] (United Kingdom)	To assess the practicality of the proposed internal pilot and full-scale trial.	Pre-trial (Feasibility)	Participants (n = 48), ear, nose and throat (ENT) consultants, 1 ET trainee (registrar), research nurses (n = 6), nurse practitioners (n = 4), trial manager (n = 2)	Tonsillectomy/deferred surgery as conservative management option	In-depth interviews Framework analysis
5. McSweeney (2017) [69]. (United Kingdom)	To determine the impact of recurrent sore throats and tonsillitis in adults and stakeholder views of treatment pathways.	Pre-trial (Feasibility)	Patients (n = 15), General Practitioners (n = 11), 9 ENT consultants, 1 specialist registrar, 6 research nurses, 4 nurse practitioners, 2 trial managers (n = 22)	Tonsillectomy/non-surgical management	In-depth interviews Framework analysis
6. Mills et al (2011) [71] (United Kingdom)	To explore how patients’ treatment preferences were expressed and justified during recruitment to a randomised controlled trial (RCT) and how they influenced participation and treatment decisions.	Main trial (Recruitment)	Participants with localised prostate cancer (n = 93)	Radical prostatectomy/ radical conformal radiotherapy/active monitoring	Audio recordings
7. Moynihan, C., et al. (2012) (United Kingdom)	To illuminate problems in the context of randomisation to a randomised controlled trial comparing selective bladder preservation against surgery in muscle invasive bladder cancer	Pre-trial (Feasibility)	Patients (n = 24)	Radical surgery (cystectomy) following neoadjuvant chemotherapy/ selective bladder preservation where definitive treatment (radiotherapy or cystectomy) was decided based on response to neoadjuvant chemotherapy	Semi-structured interviews Framework analysis
8. Paramasivan et al (2011) [73] (United Kingdom)	To explore reasons for low recruitment and attempt to improve recruitment rates by implementing changes suggested by qualitative findings.	Pre-trial (Feasibility)	Healthcare professionals (n = 9)	Radical surgery (cystectomy) following neoadjuvant chemotherapy/selective bladder preservation where definitive treatment (radiotherapy or cystectomy) was decided based on response to neoadjuvant chemotherapy	Audio recordings Semi-structured interviews Conversation analysis Thematic analysis
9. Skea, Z. C., et al. (2017) [74] (United Kingdom)	To explore trial site staff’s perceptions regarding barriers and facilitators to local recruitment.To identify trial-specific modifiable factors that could enhance the facilitators and remove the barriers to recruitment.	Main trial (Recruitment)	Members of staff from 4 trial sites (n = 11) Co-applicant (n = 1), Principal Investigators (n = 3) Consultant Urologist (n = 1), Research Nurses (n = 5), Research Assistant (n = 1)	Extracorporeal shockwave lithotripsy/ureteroscopic stone retrieval (via surgery)	Semi-structured interviews Thematic analysis using Framework approach
10. Strong et al (2016) [75] (United Kingdom)	To explore how teamwork influences recruitment to a multicentre randomised controlled trial (RCT) involving interventions delivered by different clinical specialties.	Main trial (Recruitment)	Healthcare professionals (n = 21)	Surgical (oesophagostomy)/definitive chemoradiotherapy)	Semi-structured interviews Thematic analysis
11. Thorstensson (2009) [76] (Sweden)	To understand patients' views about treatment after acute ACL injury, and to explore why patients crossed over from the training only to the surgical and training treatment arm despite consenting to participate in a trial comparing the two treatments.	Main trial	Patients (n = 34)	Arthroscopic surgical reconstruction followed by physiotherapist supervised outpatient training (exercise)/supervised training only.	In-depth interviews Framework approach
12. Zeibland et al (2007) [77] (United Kingdom)	To explore their understanding of the trial purpose and how this understanding had influenced their recruitment procedures and interpretation of the results.	Completion of study	Participating surgeons (n = 11)	Intensive functional rehabilitation programme (FRP) with spinal fusion surgery for treatment of chronic low back pain	In-depth interviews Thematic analysis
13. Wade et al (2009) [78] (United Kingdom)	To open the “black box” of what goes on during informed consent appointments in a large multicentre RCT (ProtecT).	Feasibility and main study	Recruitment appointments (n = 23) 12 recruitment staff	Radical prostatectomy, radical conformal radiotherapy and active monitoring	Audio recordings Thematic, content and conversation analysis
14. Minns Lowe (2017) [79] (United Kingdom)	To explore why participants recruited within UKUFF (The United Kingdom Rotator Cuff Tear Trial) did not remain within their allocated treatment arm, and explored crossover and decisions about having/declining surgery from the perspective of trial participants.	During study	Participants (n = 18)	Arthroscopic rotator cuff repair surgery/open/mini-open rotator cuff repair surgery/Rest then Exercise (RtE)	Semi-structured interviews Interpretative Phenomenological Analysis (IPA)
15. Griffin et al (2016) [80] (United Kingdom)	To understand how to optimise recruitment in a future full RCT of this question. Feasibility study comparing surgery and non-operative care for hip impingement.	Feasibility	Trial Management Group (n = 10) and clinicians (n = 21) RCT consultations recorded (n = 87)	Arthroscopic surgery/physiotherapy	Audio recordings In-depth semi-structured interviews Thematic analysis
16. Brookes 2003 [81] (United Kingdom)	To examine the impact of including a ‘no active intervention’ arm (called conservative management) in a RCT comparing treatments (including surgery) for men with lower urinary tract symptoms related to benign prostatic enlargement.	Main trial	Participants (n = 22) Non-participants (n = 11)	Transurethral resection of the prostate (TURP)/no active intervention (conservative treatment)/non-contact laser therapy.	In-depth semi-structured interviews Thematic analysis
17. Leighton 2012 [82] (United Kingdom)	To examine the attitudes of patients, who presented with advanced glaucoma in at least one eye, to participation in a randomised prospective trial comparing primary medical treatment with primary surgical treatment for advanced glaucoma.	Pre-trial	5 focus groups (between 4 and 8 participants)	Primary medical treatment/primary surgical treatment	Focus groups Thematic analysis
18. Mills 2003 [83] (United Kingdom)	To explore patients’ perceptions of randomisation and understand the reasons for consenting or refusing randomisation within a controversial trial of treatments for localised prostate cancer.	Main trial	Participants in ProtecT study with localised prostate cancer (n = 21)	Radical prostatectomy,/radical conformal radiotherapy/ active monitoring	In-depth interviews Constant comparison
19. Lie, M., et al. (2012) [84] (United Kingdom)	To provide insights into two strands of understanding; firstly, women’s experience of participating in research about abortion and secondly, their experience of participating in a randomised preference trial, thus having implications for the design and conduct of termination of pregnancy clinical trials.	Main trial	Participants (n = 30)	Medical/surgical termination of pregnancy	Semi-structured interviews
20. Rooshenas et al (2016) [85] (United Kingdom)	To investigate how clinicians conveyed equipoise during recruitment appointments in ongoing RCTs, with the view to identify practices that supported or hindered equipoise communication.	Main trial	Pragmatic UK based RCTs (n = 6) Clinicians recruiting to the RCTs (n = 16) Appointments in which these clinicians presented the RCT to trial eligible patients (n = 105) 2 trials included a surgical/non-surgical comparison	Trial 1: Arthroscopy with surgical manipulation/Arthroscopy alone/Active monitoring with specialist reassessment Trial 2: Neoadjuvant treatment and surgery/definitive non-surgical treatment	In-depth interviews Audio recordings Thematic and content analysis
21. Paramasivan et al (2015) [86] (United Kingdom)	To systematically investigate, quantify and qualitatively explore the imbalances in the presentation of treatments to patients.	Pre-trial (Feasibility)	RCTs (n = 2) 1 trial included in this review Recruitment appointments (n = 26) patients (n = 16) Staff (n = 20)	Chemotherapy plus surgery or radiotherapy	Semi-structured interviews Audio recordings
22. Realpe 2016 [87] (United Kingdom)	To investigate the conduct of recruitment consultations that led to participants agreeing to participate in the pilot trial of arthroscopic surgery for hip impingement compared with non-operative care.	Pre-trial (Feasibility)	Consultations (n = 92) Participants (n = 60_ (n = 34 diagnostic, n = 58 recruitment consultations)	Arthroscopic surgery/non-operative care.	Audio recordings Thematic and conversational analysis
23. Keene 2016 [88](United Kingdom)	To investigate patients’ experiences of living with a fractured ankle and experiences of being in the trial.	Main trial	Study participants (n = 36)	Closed contact casting/Open Reduction Internal fixation (ORIF)	Interviews
24. Mills et al (2014) [89] (United Kingdom)	To investigate how RCT recruiters reacted to patients’ treatment preferences and to identify key strategies to improve informed decision making and trial recruitment.	Main trial (Recruitment)	RCTs (n = 3) 2 trials within this Recruitment appointments (n = 103) participants (n = 96)	Trial 1: Surgical and non-surgical treatment for cancer Trial 2: Surgery/radiotherapy/active monitoring	Audio recordings
25. Donovan et al (2014) [91] (United Kingdom)	To understand the recruitment process from the perspective of recruiters actively recruiting RCT participants in six pragmatic RCTs and to identify opportunities for interventions to improve recruitment.	Feasibility and main trial	RCTs (n = 6) 3 trials included in this review Trial 1: Doctors (n = 3) Trial 2: Doctors (n = 13)/nurses (n = 10) Trial 3: Doctors (n = 8)/nurses (n = 3)	Trial 1: Surgery/radiotherapy Trial 2: Surgery/radiotherapy/active monitoring Trial 3: (Chemotherapy) surgery/radiotherapy	In-depth Interview Content and thematic analysis
26. Donovan et al (2014) [90] (United Kingdom)	To investigate how doctors considered and experienced the concept of equipoise whilst recruiting patients to RCTs.	Feasibility and main trial	RCTs (n = 6) 3 trials included in this review Trial 1: Doctors and nurses (n = 6) Trial 2: Doctors and nurses (n = 20) Trial 3 Doctors (n = 8)	Trial 1: Laser surgery/radiotherapy Trial 2: Surgery/radiotherapy/monitoring Trial 3: (Chemotherapy) surgery/radiotherapy	In-depth Interview Content and thematic analysis