Effectiveness of participant recruitment strategies for critical care trials: A systematic review and narrative synthesis

Abstract

Background: Critical care trials are limited by problems with participant recruitment, and little is known about the most effective ways to enhance trial participation. Despite clinical research improving in the past decades within intensive care, participant recruitment remains a challenge. Not all eligible patients are identified, and opportunities for enrolment into clinical trials are often missed. Interventions to facilitate recruitment need to be identified to improve trial conduct in the critical care environment. Therefore, we aimed to establish the effectiveness of recruitment strategies in critical care trials in order to inform future research practice. Methods: Databases including MEDLINE, Embase, CINAHL and PsycINFO were searched for English language papers from inception to February 2020. The objectives were to: (1) establish the effectiveness of recruitment strategies and (2) recommend how effective recruitment strategies can inform research practice. Two reviewers independently assessed papers for inclusion and critically appraised the quality of the studies. Discrepancies were discussed within the research team. Relevant data were extracted and thematically coded into five overarching themes using a narrative synthesis approach. The review was prospectively registered on PROSPERO (CRD42019160519). Results: The search resulted in 2509 initially identified articles, with 15 that met the inclusion criteria. Articles reported a combination of quantitative, mixed methods and qualitative studies and a range of low-, moderate- and high-quality studies. Although, in-keeping with narrative synthesis approaches, none were excluded based on methodological quality. Five themes were identified relating to: patient eligibility identification, who provides information and seeks consent, resource limitations, research culture or environment and the consent model used. The relative success of recruitment strategies was dependent upon the experience and availability of the staff involved in the approach, trial design, the application of the strategy to the specific intensive care environment, the acceptability of the recruitment and consent models used, and the efficiency of the recruitment procedures. Opportunities for consent were missed in a proportion of eligible patients in most studies, suggesting that clinicians may avoid recruiting more complex patients or in more complex situations and that further development of strategies is needed. Conclusion: More effective recruitment strategies are required to enhance recruitment and the representativeness of the patient sample obtained in critical care trials, in order to expand the evidence base for treatments in this field. Greater focus is needed on assessing the performance of different recruitment strategies within different types of studies and critical care research environments. Future research should explore key stakeholders’ experiences of, and attitudes towards, recruitment and establish the most important and feasible modifiable barriers to recruitment.

Unpacking the ‘black box of horrendousness’: a qualitative exploration of the barriers and facilitators to conducting trials involving adults lacking capacity to consent

“…The context-specific challenges identified in this study reflect those encountered in numerous previous studies exploring research in settings such as critical care [ 47 , 48 ] and care homes [ 49 ], and the issues surrounding capacity and consent in populations such as those receiving palliative and end of life care [ 50 ], people with aphasia [ 51 ] and people with learning disabilities and/or autism [ 52 ]. Our findings that highlight a universal knowledge deficit are also supported by previous studies which have examined understanding of the legal frameworks governing research involving adults who lack capacity by health and social care professionals [ 26 ], RECs [ 53 ] and researchers [ 54 , 55 ].…”

Learning from stakeholders to inform good practice guidance on consent to research in intensive care units: a mixed-methods study

“…Implementing substitute decision making also has its challenges, particularly where there is a short time window for recruitment. 3 10 Family receptivity to discussions about research in ICUs may be affected by the often sudden hospitalisation, and many relatives will be preoccupied with dealing with the emotional impact of this. Furthermore, there are situations when even substitute decision making by a relative or independent practitioner is not feasible, such as when a study is investigating under emergency situations, and delaying administration of treatment to consult with SDMs could compromise patient outcomes.…”

“…Though prospective patient informed consent is considered to be 'gold standard', a patient must be able to understand and retain the information on risks and benefits presented to them and clearly communicate their decision. [1][2][3] Yet only around 10% of ICU patients have capacity to provide informed consent. [4][5][6][7][8][9] The use of substitute decision makers (SDMs) to facilitate inclusion of incapacitated patients has been developed to balance the rights and welfare of the patient with the necessity of conducting research.…”

“…Clinical research in intensive care units (ICUs) is a vital aspect of medical practice, but obtaining informed consent from patients prior to their enrolment in a study is often not possible and recruitment is therefore ethically complex. Though prospective patient informed consent is considered to be ‘gold standard’, a patient must be able to understand and retain the information on risks and benefits presented to them and clearly communicate their decision 1–3. Yet only around 10% of ICU patients have capacity to provide informed consent 4–9.…”

Exploring the inclusion of under-served groups in trials methodology research: an example from ethnic minority populations’ views on deferred consent

“…Typically, this method is used when the intervention is required urgently but the patient lacks the capacity to consent to research and there is no time to involve a surrogate-decision maker to consent on their behalf. This includes in prehospital ambulance research [1], in critical care settings [2], and in a number of high-profile COVID-19 studies [3]. In such circumstances, if capacity and an ability to understand the study information is regained during the study, patients are then informed and consent is sought for continued participation or withdrawal from the study, or a surrogate is approached on their behalf [4].…”