The ethics of Zelen consent

Nephron Sparing Treatment (NEST) for Small Renal Masses: A Feasibility Cohort-embedded Randomised Controlled Trial Comparing Percutaneous Cryoablation and Robot-assisted Partial Nephrectomy

There is a paucity of high-level evidence on small renal mass (SRM) management, as previous classical randomised controlled trials (RCTs) failed to meet accrual targets. Our objective was to assess the feasibility of recruitment to a cohort-embedded RCT comparing cryoablation (CRA) to robotic partial nephrectomy (RPN). A total of 200 participants were recruited to the cohort, of whom 50 were enrolled in the RCT. In the CRA intervention arm, 84% consented (95% confidence interval [CI] 64-95%) and 76% (95% CI 55-91%) received CRA; 100% (95% CI 86-100%) of the control arm underwent RPN. The retention rate was 90% (95% CI 79-96%) at 6 mo. In the RPN group 2/25 (8%) were converted intra-operative to radical nephrectomy. Postoperative complications (Clavien-Dindo grade 1-2) occurred in 12% of the CRA group and 29% of the RPN group. The median length of hospital stay was shorter for CRA (1 vs 2 d; p = 0.019). At 6 mo, the mean change in renal function was -5.0 ml/min/1.73 m2 after CRA and -5.8 ml/min/1.73 m2 after RPN. This study demonstrates the feasibility of a cohort-embedded RCT comparing CRA and RPN. These data can be used to inform multicentre trials on SRM management. PATIENT SUMMARY: We assessed whether patients with a small kidney tumour would consent to a trial comparing two different treatments: cryoablation (passing small needles through the skin to freeze the kidney tumour) and surgery to remove part of the kidney. We found that most patients agreed and a full trial would therefore be feasible.

When does the placebo effect have an impact on network meta-analysis results?

The placebo effect is the 'effect of the simulation of treatment that occurs due to a participant's belief or expectation that a treatment is effective'. Although the effect might be of little importance for some conditions, it can have a great role in others, mostly when the evaluated symptoms are subjective. Several characteristics that include informed consent, number of arms in a study, the occurrence of adverse events and quality of blinding may influence response to placebo and possibly bias the results of randomised controlled trials. Such a bias is inherited in systematic reviews of evidence and their quantitative components, pairwise meta-analysis (when two treatments are compared) and network meta-analysis (when more than two treatments are compared). In this paper, we aim to provide red flags as to when a placebo effect is likely to bias pairwise and network meta-analysis treatment effects. The classic paradigm has been that placebo-controlled randomised trials are focused on estimating the treatment effect. However, the magnitude of placebo effect itself may also in some instances be of interest and has also lately received attention. We use component network meta-analysis to estimate placebo effects. We apply these methods to a published network meta-analysis, examining the relative effectiveness of four psychotherapies and four control treatments for depression in 123 studies.

Decompressive craniectomy for the treatment of high intracranial pressure in closed traumatic brain injury

BACKGROUND

High intracranial pressure (ICP) is the most frequent cause of death and disability after severe traumatic brain injury (TBI). It is usually treated with general maneuvers (normothermia, sedation, etc.) and a set of first-line therapeutic measures (moderate hypocapnia, mannitol, etc.). When these measures fail, second-line therapies are initiated, which include: barbiturates, hyperventilation, moderate hypothermia, or removal of a variable amount of skull bone (secondary decompressive craniectomy).

OBJECTIVES

To assess the effects of secondary decompressive craniectomy (DC) on outcomes of patients with severe TBI in whom conventional medical therapeutic measures have failed to control raised ICP.

SEARCH METHODS

The most recent search was run on 8 December 2019. We searched the Cochrane Injuries Group's Specialised Register, CENTRAL (Cochrane Library), Ovid MEDLINE(R), Ovid MEDLINE(R) In-Process & Other Non-Indexed Citations, Ovid MEDLINE(R) Daily and Ovid OLDMEDLINE(R), Embase Classic + Embase (OvidSP) and ISI Web of Science (SCI-EXPANDED & CPCI-S). We also searched trials registries and contacted experts.

SELECTION CRITERIA

We included randomized studies assessing patients over the age of 12 months with severe TBI who either underwent DC to control ICP refractory to conventional medical treatments or received standard care.

DATA COLLECTION AND ANALYSIS

We selected potentially relevant studies from the search results, and obtained study reports. Two review authors independently extracted data from included studies and assessed risk of bias. We used a random-effects model for meta-analysis. We rated the quality of the evidence according to the GRADE approach.

MAIN RESULTS

We included three trials (590 participants). One single-site trial included 27 children; another multicenter trial (three countries) recruited 155 adults, the third trial was conducted in 24 countries, and recruited 408 adolescents and adults. Each study compared DC combined with standard care (this could include induced barbiturate coma or cooling of the brain, or both). All trials measured outcomes up to six months after injury; one also measured outcomes at 12 and 24 months (the latter data remain unpublished). All trials were at a high risk of bias for the criterion of performance bias, as neither participants nor personnel could be blinded to these interventions. The pediatric trial was at a high risk of selection bias and stopped early; another trial was at risk of bias because of atypical inclusion criteria and a change to the primary outcome after it had started. Mortality: pooled results for three studies provided moderate quality evidence that risk of death at six months was slightly reduced with DC (RR 0.66, 95% CI 0.43 to 1.01; 3 studies, 571 participants; I2 = 38%; moderate-quality evidence), and one study also showed a clear reduction in risk of death at 12 months (RR 0.59, 95% CI 0.45 to 0.76; 1 study, 373 participants; high-quality evidence). Neurological outcome: conscious of controversy around the traditional dichotomization of the Glasgow Outcome Scale (GOS) scale, we chose to present results in three ways, in order to contextualize factors relevant to clinical/patient decision-making. First, we present results of death in combination with vegetative status, versus other outcomes. Two studies reported results at six months for 544 participants. One employed a lower ICP threshold than the other studies, and showed an increase in the risk of death/vegetative state for the DC group. The other study used a more conventional ICP threshold, and results favoured the DC group (15.7% absolute risk reduction (ARR) (95% CI 6% to 25%). The number needed to treat for one beneficial outcome (NNTB) (i.e. to avoid death or vegetative status) was seven. The pooled result for DC compared with standard care showed no clear benefit for either group (RR 0.99, 95% CI 0.46 to 2.13; 2 studies, 544 participants; I2 = 86%; low-quality evidence). One study reported data for this outcome at 12 months, when the risk for death or vegetative state was clearly reduced by DC compared with medical treatment (RR 0.68, 95% CI 0.54 to 0.86; 1 study, 373 participants; high-quality evidence). Second, we assessed the risk of an 'unfavorable outcome' evaluated on a non-traditional dichotomized GOS-Extended scale (GOS-E), that is, grouping the category 'upper severe disability' into the 'good outcome' grouping. Data were available for two studies (n = 571). Pooling indicated little difference between DC and standard care regarding the risk of an unfavorable outcome at six months following injury (RR 1.06, 95% CI 0.69 to 1.63; 544 participants); heterogeneity was high, with an I2 value of 82%. One trial reported data at 12 months and indicated a clear benefit of DC (RR 0.81, 95% CI 0.69 to 0.95; 373 participants). Third, we assessed the risk of an 'unfavorable outcome' using the (traditional) dichotomized GOS/GOS-E cutoff into 'favorable' versus 'unfavorable' results. There was little difference between DC and standard care at six months (RR 1.00, 95% CI 0.71 to 1.40; 3 studies, 571 participants; low-quality evidence), and heterogeneity was high (I2 = 78%). At 12 months one trial suggested a similar finding (RR 0.95, 95% CI 0.83 to 1.09; 1 study, 373 participants; high-quality evidence). With regard to ICP reduction, pooled results for two studies provided moderate quality evidence that DC was superior to standard care for reducing ICP within 48 hours (MD -4.66 mmHg, 95% CI -6.86 to -2.45; 2 studies, 182 participants; I2 = 0%). Data from the third study were consistent with these, but could not be pooled. Data on adverse events are difficult to interpret, as mortality and complications are high, and it can be difficult to distinguish between treatment-related adverse events and the natural evolution of the condition. In general, there was low-quality evidence that surgical patients experienced a higher risk of adverse events.

AUTHORS' CONCLUSIONS

Decompressive craniectomy holds promise of reduced mortality, but the effects of long-term neurological outcome remain controversial, and involve an examination of the priorities of participants and their families. Future research should focus on identifying clinical and neuroimaging characteristics to identify those patients who would survive with an acceptable quality of life; the best timing for DC; the most appropriate surgical techniques; and whether some synergistic treatments used with DC might improve patient outcomes.

Ethical Acceptability of Postrandomization Consent in Pragmatic Clinical Trials

IMPORTANCE

Pragmatic clinical trials that seek informed consent after randomization (ie, postrandomization consent) are increasingly used, but debate on ethics persists because control arm patients are not specifically informed about the trials and randomization occurs before consent for the trials. The public's attitude toward postrandomization consent trials is unknown, but the way the trials are described could bias people's views.

OBJECTIVES

To assess the attitudes of the US general public toward postrandomization informed consent for pragmatic trials and to measure potential framing and other factors associated with those attitudes.

DESIGN, SETTING, AND PARTICIPANTS

An online, 2 × 2 experimental survey (fielded between February 23 and April 3, 2018) portraying 4 scenarios of postrandomization informed consent (with prior broad consent for medical record use) was conducted. These scenarios included traditional randomized clinical trial language framing vs alternative framing in a high-stakes trial (ie, survival in leukemia) or low-stakes trial (ie, blood glucose level in diabetes). A total of 3793 individuals invited to participate were part of an existing panel representative of the US general public (GfK KnowledgePanel).

MAIN OUTCOMES AND MEASURES

The proportion of participants who would recommend that an ethics review board approve a postrandomization consent pragmatic trial.

RESULTS

A total of 2042 of 3739 invitees (54.6%) responded; after exclusion of 38 incomplete surveys, 2004 participants were included in the analysis. Of these, 997 (49.8%) were women, 1440 (71.9%) were white non-Hispanic, 199 (9.9%) were black non-Hispanic, and 233 (11.6%) were Hispanic. Mean (SD) age was 47.5 (17.4) years. Across scenarios, weighted data showed that 75.4% of the participants would recommend approval of the postrandomization consent pragmatic trial, 20.4% would probably not recommend approval, and 4.2% would definitely not recommend approval. Approval was not sensitive to framing language (traditional vs new framing in high-stakes scenario, 74.3% vs 76.8%, P = .40; in low-stakes scenario, 77.7% vs 72.9%, P = .10) or to the stakes (low vs high stakes in traditional framing, 77.7% vs 74.3%, P = .25; in new framing, 72.9% vs 76.8%, P = .18). Better understanding of the postrandomization consent design was associated with higher rate of approval (78.1% vs 65.0%, P = .002 for high-stakes scenario; 77.2% vs 64.9%, P = .004 for low-stakes scenario), especially among those with less education. However, opinions about personal involvement in the control arm were more cautious (range depending on scenario, 45.6%-59.7%) and sensitive to stakes but not to framing.

CONCLUSIONS AND RELEVANCE

The public's generally high rate of approval of the ethics of postrandomization informed consent for pragmatic trial designs does not appear to be affected by whether postrandomization consent design is framed using traditional randomized clinical trial terminology, regardless of the stakes of the trial. Promoting better understanding of the design may increase its acceptance by the public.

Dexamethasone for Cardiac Surgery trial (DECS-II): Rationale and a novel, practice preference-randomized consent design

BACKGROUND

Numerous studies have investigated high-dose corticosteroids in cardiac surgery, but with mixed results leading to ongoing variations in practice around the world. DECS-II is a study comparing high-dose dexamethasone with placebo in patients undergoing cardiac surgery.

METHODS

We discuss the rationale for conducting DECS-II, a 2800-patient, pragmatic, multicenter, assessor-blinded, randomized trial in cardiac surgery, and the features of the DECS-II study design (objectives, end points, target population, based on practice preference with post-randomization consent, treatments, patient follow-up and analysis).

CONCLUSIONS

The DECS-II trial will use a novel, efficient trial design to evaluate whether high-dose dexamethasone has a patient-centered benefit of enhancing recovery and increasing the number of days at home after cardiac surgery.

Commentary: considerations for using the 'Trials within Cohorts' design in a clinical trial of an investigational medicinal product

Background

The ‘trials within cohorts’ (TwiC) design is a pragmatic approach to randomised trials in which trial participants are randomly selected from an existing cohort. The design has multiple potential benefits, including the option of conducting multiple trials within the same cohort.

Main text

To date, the TwiC design methodology been used in numerous clinical settings but has never been applied to a clinical trial of an investigational medicinal product (CTIMP). We have recently secured the necessary approvals to undertake the first CTIMP using the TwiC design. In this paper, we describe some of the considerations and modifications required to ensure such a trial is compliant with Good Clinical Practice and international clinical trials regulations.

We advocate using a two-stage consent process and using the consent stages to explicitly differentiate between trial participants and cohort participants who are providing control data. This distinction ensured compliance but had consequences with respect to costings, recruitment and the trial assessment schedule.

Conclusion

We have demonstrated that it is possible to secure ethical and regulatory approval for a CTIMP TwiC. By including certain considerations at the trial design stage, we believe this pragmatic and efficient methodology could be utilised in other CTIMPs in future.

Electronic supplementary material

The online version of this article (doi:10.1186/s13063-017-2432-3) contains supplementary material, which is available to authorized users.

Methods for assessing and controlling placebo effects

The placebo serves as an indispensable control in many randomized trials. When analyzing the benefit of a new treatment, researchers are often confronted with large placebo effects that diminish the treatment effect. Various alternative methods have been proposed for analyzing placebo and treatment effects in studies where large placebo effects are expected or have already occurred. This paper presents an overview of methodological work that has been proposed for assessing and/or controlling for placebo effects in randomized trials. Throughout this paper, two main approaches are discussed. The first approach considers designs that represent alternatives to the classical placebo-controlled randomized trial design. Separately, the second approach considers adopting new methods for the statistical analysis of placebo and treatment effects to be implemented after the data have been collected using a classical randomized trial design.

The cohort multiple randomized controlled trial design was found to be highly susceptible to low statistical power and internal validity biases

Objectives

The “cohort multiple randomized controlled trial” (cmRCT) is a recent innovation by which novel interventions are trialed within large longitudinal cohorts of patients to gain efficiencies and align trials more closely to standard clinical practice. The use of cmRCTs is outpacing its methodological understanding, and more appropriate methods for designing and analyzing such trials are urgently needed.

Study Design and Setting

We established the UK Comprehensive Longitudinal Assessment of Salford Integrated Care cohort of 4,377 patients with long-term conditions within which we are conducting a cmRCT (“Proactive Telephone Coaching and Tailored Support”) of telephone-based health coaching.

Results

We identify some key methodological challenges to the use of the cmRCT in actual practice. Principal are issues around statistical power, sample size, and treatment effect estimation, for which we provide appropriate methods. Sampling procedures commonly applied in conventional RCTs can result in unintentional selection bias. The fixed data collection points that feature in cmRCTs can also threaten validity.

Conclusion

The cmRCT may offer advantages over conventional trial designs. However, a cmRCT requires appropriate power calculation, sampling, and analysis procedures; else, studies may be underpowered or subject to validity biases. We offer solutions to some of the key issues, but further methodological investigations are needed. Cohort multiple RCT–specific Consolidated Standards of Reporting Trials guidance may be indicated.

Ethics and practice of Trials within Cohorts: An emerging pragmatic trial design

BACKGROUND

With increasing emphasis on pragmatic trials, new randomized clinical trial designs are being proposed to enhance the "real world" nature of the data generated. We describe one such design, appropriate for unmasked pragmatic clinical trials in which the control arm receives usual care, called "Trials within Cohorts" that is increasingly used in various countries because of its efficiency in recruitment, advantages in reducing subject burden, and ability to better mimic real-world consent processes.

METHODS

Descriptive, ethical, and US regulatory analysis of the Trials within Cohorts design.

RESULTS

Trials within Cohorts design involves, after recruitment into a cohort, randomization of eligible subjects, followed by an asymmetric treatment of the two arms: those selected for the experimental arm provide informed consent for the intervention trial, while the data from the control arm are used based on prior broad permission. Thus, unlike the traditional Zelen post-randomization consent design, the cohort participants are informed about future research within the cohort; however, the extent of this disclosure currently varies among studies. Thus, ethical analysis is provided for two types of situations: when the pre-randomization disclosure and consent regarding the embedded trials are fairly explicit and detailed versus when they consist of only general statements about future data use. These differing ethical situations could have implications for how ethics review committees apply US research rules regarding waivers and alterations of informed consent.

CONCLUSION

Trials within Cohorts is a promising new pragmatic randomized controlled trial design that is being increasingly used in various countries. Although the asymmetric consent procedures for the experimental versus control arm subjects can initially raise ethical concerns, it is ethically superior to previous post-randomization consent designs and can have important advantages over traditional trial designs.

Exceptions to the rule of informed consent for research with an intervention

BACKGROUND

In specific situations it may be necessary to make an exception to the general rule of informed consent for scientific research with an intervention. Earlier reviews only described subsets of arguments for exceptions to waive consent.

METHODS

Here, we provide a more extensive literature review of possible exceptions to the rule of informed consent and the accompanying arguments based on literature from 1997 onwards, using both Pubmed and PsycINFO in our search strategy.

RESULTS

We identified three main categories of arguments for the acceptability of a consent waiver: data validity and quality, major practical problems, and distress or confusion of participants. Approval by a medical ethical review board always needs to be obtained. Further, we provide examples of specific conditions under which consent waiving might be allowed, such as additional privacy protection measures.

CONCLUSIONS

The reasons legitimized by the authors of the papers in this overview can be used by researchers to form their own opinion about requesting an exception to the rule of informed consent for their own study. Importantly, rules and guidelines applicable in their country, institute and research field should be followed. Moreover, researchers should also take the conditions under which they feel an exception is legitimized under consideration. After discussions with relevant stakeholders, a formal request should be sent to an IRB.

Usability testing, initial implementation, and formative evaluation of an evidence-based intervention: lessons from a demonstration project to reduce long-term foster care

The field of child welfare faces an undersupply of evidence-based interventions to address long-term foster care. The Permanency Innovations Initiative is a five-year federal demonstration project intended to generate evidence to reduce long stays in foster care for those youth who encounter the most substantial barriers to permanency. This article describes a systematic and staged approach to implementation and evaluation of a PII project that included usability testing as one of its key activities. Usability testing is an industry-derived practice which analyzes early implementation processes and evaluation procedures before they are finalized. This article describes the iterative selection, testing, and analysis of nine usability metrics that were designed to assess three important constructs of the project's initial implementation and evaluation: intervening early, obtaining consent, and engaging parents. Results showed that seven of nine metrics met a predetermined target. This study demonstrates how findings from usability testing influenced the initial implementation and formative evaluation of an evidence-supported intervention. Implications are discussed for usability testing as a quality improvement cycle that may contribute to better operationalized interventions and more reliable, valid, and replicable evidence.

Decompressive craniectomy for the treatment of refractory high intracranial pressure in traumatic brain injury

BACKGROUND

High intracranial pressure (ICP) is the most frequent cause of death and disability after severe traumatic brain injury (TBI). High ICP is treated by general maneuvers (normothermia, sedation etc) and a set of first line therapeutic measures (moderate hypocapnia, mannitol etc). When these measures fail to control high ICP, second line therapies are started. Among these, second line therapies such as barbiturates, hyperventilation, moderate hypothermia or removal of a variable amount of skull bone (known as decompressive craniectomy) are used.

OBJECTIVES

To assess the effects of secondary decompressive craniectomy (DC) on outcome and quality of life in patients with severe TBI in whom conventional medical therapeutic measures have failed to control raised ICP.

SEARCH STRATEGY

We searched the Cochrane Injuries Group's Trial Register, CENTRAL, MEDLINE, EMBASE, Best Evidence, Clinical Practice Guidelines, PubMed, CINAHL, the National Research Register and Google Scholar. We also handsearched relevant conference proceedings and contacted experts in the field and the authors of included studies.

SELECTION CRITERIA

Randomized or quasi-randomized studies assessing patients over the age of 12 months with a severe TBI who underwent DC to control ICP refractory to conventional medical treatments.

DATA COLLECTION AND ANALYSIS

Two authors independently examined the electronic search results for reports of possibly relevant trials and for retrieval in full. One author applied the selection criteria, performed the data extraction and assessed methodological quality. Study authors were contacted for additional information.

MAIN RESULTS

We found one trial with 27 participants conducted in the pediatric population (>18 years). DC was associated with a risk ratio (RR) for death of 0.54 (95% CI 0.17 to 1.72), and RR of 0.54 for death, vegetative status or severe disability 6 to 12 months after injury (95% CI 0.29 to 1.07).

AUTHORS' CONCLUSIONS

There is no evidence to support the routine use of secondary DC to reduce unfavourable outcome in adults with severe TBI and refractory high ICP. In the pediatric population DC reduces the risk of death and unfavourable outcome. Despite the wide confidence intervals for death and the small sample size of the only study identified, this treatment maybe justified in patients below the age of 18 when maximal medical treatment has failed to control ICP. To date, there are no results from randomised trials to confirm or refute the effectiveness of DC in adults. However, the results of non-randomized trials and controlled trials with historical controls involving adults, suggest that DC may be a useful option when maximal medical treatment has failed to control ICP. There are two ongoing randomized controlled trials of DC (Rescue ICP and DECRAN) that may allow further conclusions on the efficacy of this procedure in adults.

Thrombosis and Cancer: The Role of Screening for Occult Cancer and Recognizing the Underlying Biological Mechanisms

The association between cancer and thrombosis is well recognized. What is not known, however, is the exact relationship between these two common medical conditions. Although the development of venous thromboembolism (VTE) in a patient with known cancer is the most common presentation, in some patients, VTE may precede the diagnosis of malignancy by many months. The variation in clinical presentation is likely due to the heterogeneous biology of different tumor types and also reflects the limitations of detection or available diagnostic methods. Accumulating evidence now suggests that critical oncogenic events may also trigger activation of the coagulation cascade, leading to a prothrombotic environment that not only manifests as venous thromboembolic disease but also promotes the growth and progression of the malignancy. This chapter will review the evidence for screening for occult malignancy in patients presenting with unprovoked or idiopathic thrombosis, briefly outline the known biological relationships between malignancy and thrombosis, and summarize the clinical data on the potential anticancer effects of low molecular weight heparins (LMWHs).