Trials using deferred consent in the emergency setting: a systematic review and narrative synthesis of stakeholders’ attitudes

Abstract

Background Patients with acute conditions often lack the capacity to provide informed consent, and narrow therapeutic windows mean there is no time to seek consent from surrogates prior to treatment being commenced. One method to enable the inclusion of this study population in emergency research is through recruitment without prior consent, often known as ‘deferred consent’. However, empirical studies have shown a large disparity in stakeholders’ opinions regarding this enrolment method. This systematic review aimed to understand different stakeholder groups’ attitudes to deferred consent, particularly in relation to the context in which deferred consent might occur. Methods Databases including MEDLINE, EMCare, PsychINFO, Scopus, and HMIC were searched from 1996 to January 2021. Eligible studies focussed on deferred consent processes for adults only, in the English language, and reported empirical primary research. Studies of all designs were included. Relevant data were extracted and thematically coded using a narrative approach to ‘tell a story’ of the findings. Results Twenty-seven studies were included in the narrative synthesis. The majority examined patient views (n = 19). Data from the members of the public (n = 5) and health care professionals (n =5) were also reported. Four overarching themes were identified: level of acceptability of deferred consent, research-related factors influencing acceptability, personal characteristics influencing views on deferred consent, and data use after refusal of consent or participant death. Conclusions This review indicates that the use of deferred consent would be most acceptable to stakeholders during low-risk emergency research with a narrow therapeutic window and where there is potential for patients to benefit from their inclusion. While the use of narrative synthesis allowed assessment of the included studies, heterogeneous outcome measures meant that variations in study results could not be reliably attributed to the different trial characteristics. Future research should aim to develop guidance for research ethics committees when reviewing trials using deferred consent in emergency research and investigate more fully the views of healthcare professionals which to date have been explored less than patients and members of the public. Trial registration PROSPERO CRD42020223623

Protocol for Deferral of Consent in Acute Stroke Trials

“…(24) In the 8 years since, many more trials have employed deferral of consent, including as the exclusive method of enrollment, as in AcT,(34) SWIFT DIRECT, (25) ULTRA, (26) and others. (27) Despite its frequent use in recent stroke trials, trial protocols have not offered a standardized approach to justifying the use of deferral, meaning they have not explicitly stated why it was required. In their review, Feldman et al identified mentions of the presence of REB approval (as in HASTA, IST-3, SYNTHESIS-Expansion), of the need for rapid treatment (as in INSULINFARCT, PIL-FAST), of the right of patients to not have alteplase withheld (PHANTOM-S), and of the ability of medical professionals to provide surrogate consent (RIGHT).…”

“…25 In the 8 years since, many more trials have used deferral of consent, including as the exclusive method of enrollment, as in AcT, 19 Solitaire With the Intention for Thrombectomy Plus Intravenous tPA vs DIRECT Solitaire Stent-Retriever Thrombectomy in Acute Anterior Circulation Stroke (SWIFT-DIRECT), 26 Ultra Early Tranexamic Acid After Subarachnoid Hemorrhage (ULTRA), 27 and others. 28 Despite its frequent use in recent stroke trials, trial protocols have not offered a standardized approach to justifying the use of deferral, meaning they have not explicitly stated why it was required. In their review, Feldman et al 25 Advanced Unresectable or Metastatic Gastric or Gastroesophageal Junction (GEJ) Adenocarcinoma (SPOTLIGHT) made explicit statements of justification, citing the potential to increase enrollment and enable study participation for more severely affected patients.…”

Complex and alternate consent pathways in clinical trials: methodological and ethical challenges encountered by underserved groups and a call to action

“…An animation aimed at adults enrolled in emergency care research which describes RWPC was developed by another research team (CoMMiTED Study) [108]. Systematic reviews have explored stakeholders' views about the acceptability of RWPC [109], including ethnic minority populations' views [110]. Such studies have found that RWPC is generally acceptable to patients, families, and practitioners, but highlighted the importance of contextual factors.…”

“…The need for more guidance for RECs who are reviewing emergency and urgent care trials, and support for consent processes for patients and members of the public who join research teams and advise on studies, has also been highlighted [106,109,117].…”

Optimizing patient recruitment into clinical trials of antimicrobial-resistant pathogens

“…Since severe infections are emergencies, and treatment options for AMR pathogens are limited, deferred consent procedures may be also considered for these trials. 19 …”