The paradox of equipoise: the principle that drives and limits therapeutic discoveries in clinical research

Gothenburg Breast reconstruction (GoBreast) II protocol: a Swedish partially randomised patient preference, superiority trial comparing autologous and implant-based breast reconstruction

INTRODUCTION

Although breast reconstruction is an integral part of breast cancer treatment, there is little high-quality evidence to indicate which method is the most effective. Randomised controlled trials (RCTs) are generally thought to provide the most solid scientific evidence, but there are significant barriers to conducting RCTs in breast reconstruction, making both recruitment and achieving unbiased and generalisable results a challenge. The objective of this study is to compare implant-based and autologous breast reconstruction in non-irradiated patients. Moreover, the study aims to improve the evidence for trial decision-making in breast reconstruction.

METHODS AND ANALYSIS

The study design partially randomised patient preference trial might be a way to overcome the aforementioned challenges. In the present study, patients who consent to randomisation will be randomised to implant-based and autologous breast reconstruction, whereas patients with strong preferences will be able to choose the method. The study is designed as a superiority trial based on the patient-reported questionnaire BREAST-Q and 124 participants will be randomised. In the preference cohort, patients will be included until 62 participants have selected the least popular alternative. Follow-up will be 60 months. Embedded qualitative studies and within-trial economic evaluation will be performed. The primary outcome is patient-reported breast-specific quality of life/satisfaction, and the secondary outcomes are complications, factors affecting satisfaction and cost-effectiveness.

ETHICS AND DISSEMINATION

The study has been approved by the Swedish Ethical Review Authority (2023-04754-01). Results will be published in peer-reviewed scientific journals and presented at peer-reviewed scientific meetings.

TRIAL REGISTRATION NUMBER

NCT06195865.

A systematic review of randomised controlled trials in breast reconstruction

BACKGROUND

For preference sensitive treatments, such as breast reconstructions, there are barriers to conducting randomised controlled trials (RCTs). The primary aims of this systematic review were to investigate what type of research questions are explored by RCTs in breast reconstruction, where have they been performed and where have they been published, and to thematise the research questions and thus create an overview of the state of the research field.

METHODS

Randomised controlled trials investigating any aspect of breast reconstructions were included. The PubMed database was searched with a pre-defined search string. Inclusion and data abstraction was performed in a pre-defined standardised fashion. For the purpose of this study, we defined key issues as comparison of categories of breast reconstruction and comparison of immediate and delayed breast reconstruction, when the thematisation was done.

RESULTS

A total of 419 abstracts were retrieved from the search. Of the 419, 310 were excluded as they were not RCTs concerning some aspect of breast reconstruction, which left us with 110 abstracts to be included in the study. The research questions of the included studies could more or less be divided into seven different themes inclusive of 2 key issues: Other issues - comparison of different categories of breast reconstruction, comparison of immediate and delayed breast reconstruction, surgical details within a category of breast reconstruction, surgical details valid for several categories of breast reconstruction, donor site management, anaesthetics, and non-surgical details. Only five studies compared key issues, and they all illustrate the challenges with RCTs in breast reconstruction.

CONCLUSIONS

A total of 110 publications based on RCTs in breast reconstruction have been published. Seven themes of research questions could be identified. Only five studies have explored the key issues. Better scientific evidence is needed for the key issues in breast reconstruction, for example by implementing a new study design in the field.

The impact of feedback training on prediction of cancer clinical trial results

INTRODUCTION

Funders must make difficult decisions about which squared treatments to prioritize for randomized trials. Earlier research suggests that experts have no ability to predict which treatments will vindicate their promise. We tested whether a brief training module could improve experts' trial predictions.

METHODS

We randomized a sample of breast cancer and hematology-oncology experts to the presence or absence of a feedback training module where experts predicted outcomes for five recently completed randomized controlled trials and received feedback on accuracy. Experts then predicted primary outcome attainment for a sample of ongoing randomized controlled trials. Prediction skill was assessed by Brier scores, which measure the average deviation between their predictions and actual outcomes. Secondary outcomes were discrimination (ability to distinguish between positive and non-positive trials) and calibration (higher predictions reflecting higher probability of trials being positive).

RESULTS

A total of 148 experts (46 for breast cancer, 54 for leukemia, and 48 for lymphoma) were randomized between May and December 2017 and included in the analysis (1217 forecasts for 25 trials). Feedback did not improve prediction skill (mean Brier score for control: 0.22, 95% confidence interval = 0.20-0.24 vs feedback arm: 0.21, 95% confidence interval = 0.20-0.23; p = 0.51). Control and feedback arms showed similar discrimination (area under the curve = 0.70 vs 0.73, p = 0.24) and calibration (calibration index = 0.01 vs 0.01, p = 0.81). However, experts in both arms offered predictions that were significantly more accurate than uninformative forecasts of 50% (Brier score = 0.25).

DISCUSSION

A short training module did not improve predictions for cancer trial results. However, expert communities showed unexpected ability to anticipate positive trials.Pre-registration record: https://aspredicted.org/4ka6r.pdf.

A systematic review of the scientific evidence of venous supercharging in autologous breast reconstruction with abdominally based flaps

BACKGROUND

Abdominally based free flaps are commonly used in breast reconstruction. A frequent complication is venous congestion, which might contribute to around 40% of flap failures. One way to deal with it is venous supercharging. The primary aim of this study was to investigate the scientific evidence for the effects of venous supercharging.

METHODS

A systematic literature search was conducted in PubMed, CINAHL, Embase, and Cochrane library. The included articles were critically appraised, and certainty of evidence was assessed using the Grading of Recommendations, Assessment, Development and Evaluations (GRADE) approach.

RESULTS

Thirty-six studies were included. Most studies had serious study limitations and problems with directness. Three studies report 'routine' use of venous supercharging and performed it prophylactically in patients who did not have clinical signs of venous congestion. Seventeen studies report on flap complications, of which one is a randomised controlled trial demonstrating statistically significant lower complication rates in the intervention group. The overall certainty of evidence for the effect of a venous supercharging on flap complications, length of hospital stay and operative time, in patients without clinical signs of venous congestion, is very low (GRADE ⊕ ⊕ ⊝ ⊝), and low on and surgical takebacks (GRADE ⊕ ⊕ ⊝ ⊝). Twenty-one studies presented data on strategies and overall certainty of evidence for using radiological findings, preoperative measurements, and clinical risk factors to make decisions on venous supercharging is very low (GRADE ⊕ ⊝ ⊝ ⊝).

CONCLUSION

There is little scientific evidence for how to predict in which cases, without clinical signs of venous congestion, venous supercharging should be performed. The complication rate might be lower in patients in which a prophylactic venous anastomosis has been performed.

TRIAL REGISTRATION

PROSPERO (CRD42022353591).

Response-adaptive randomization for multiarm clinical trials using context-dependent information measures

Theoretical-information approach applied to the clinical trial designs appeared to bring several advantages when tackling a problem of finding a balance between power and expected number of successes (ENS). In particular, it was shown that the built-in parameter of the weight function allows finding the desired trade-off between the statistical power and number of treated patients in the context of small population Phase II clinical trials. However, in real clinical trials, randomized designs are more preferable. The goal of this research is to introduce randomization to a deterministic entropy-based sequential trial procedure generalized to multiarm setting. Several methods of randomization applied to an entropy-based design are investigated in terms of statistical power and ENS. Namely, the four design types are considered: (a) deterministic procedures, (b) naive randomization using the inverse of entropy criteria as weights, (c) block randomization, and (d) randomized penalty parameter. The randomized entropy-based designs are compared to randomized Gittins index (GI) and fixed randomization (FR). After the comprehensive simulation study, the following conclusion on block randomization is made: for both entropy-based and GI-based block randomization designs the degree of randomization induced by forward-looking procedures is insufficient to achieve a decent statistical power. Therefore, we propose an adjustment for the forward-looking procedure that improves power with almost no cost in terms of ENS. In addition, the properties of randomization procedures based on randomly drawn penalty parameter are also thoroughly investigated.

Surgeon's steering behaviour towards patients to participate in a cluster randomised trial on active surveillance for oesophageal cancer: A qualitative study

INTRODUCTION

Few studies have been conducted into how physicians use steering behaviour that may persuade patients to choose for a particular treatment, let alone to participate in a randomised trial. The aim of this study is to assess if and how surgeons use steering behaviour in their information provision to patients in their choice to participate in a stepped-wedge cluster randomised trial investigating an organ sparing treatment in (curable) oesophageal cancer (SANO trial).

MATERIALS AND METHODS

A qualitative study was performed. Thematic content analysis was applied to audiotaped and transcribed consultations of twenty patients with eight different oncological surgeons in three Dutch hospitals. Patients could choose to participate in a clinical trial in which an experimental treatment of 'active surveillance' (AS) was offered. Patients who did not want to participate underwent standard treatment: neoadjuvant chemoradiotherapy followed by oesophagectomy.

RESULTS

Surgeons used various techniques to steer patients towards one of the two options, mostly towards AS. The presentation of pros and cons of treatment options was imbalanced: positive framing of AS was used to steer patients towards the choice for AS, and negative framing of AS to make the choice for surgery more attractive. Further, steering language, i.e. suggestive language, was used, and surgeons seemed to use the timing of the introduction of the different treatment options, to put more focus on one of the treatment options.

CONCLUSION

Awareness of steering behaviour can help to guide physicians in more objectively informing patients on participation in future clinical trials.

Review of Clinical Equipoise: Examples from Oncology Trials

BACKGROUND

The current standards that govern clinical research have been shaped over the years through many historical, social, and political events. The third principle of the Belmont Report, Justice, guides the scientific community toward the equal distribution of benefits and risks in research involving human subjects. Clinical equipoise is the status of genuine uncertainty by the investigator about the superiority of one treatment arm over the other. The term clinical equipoise was proposed to provide an ethical ground to conduct randomized controlled clinical trials.

OBJECTIVE

The objective of this review is to provide the reader with an overview of the emergence of the term equipoise and its utilization in randomized controlled trials.

METHODS

In the current review article, the major oncology clinical trials and relevant patents were reviewed for the application/utilization of clinical equipoise.

RESULTS

The concept of clinical equipoise has been challenged, and different alternatives were proposed. Yet, these alternatives received numerous critiques and failed to fully replace equipoise. In addition, several patents related to anticancer agents tested in the described studies were examined. No specific reference was made as part of the patent to the status of clinical equipoise. Alternatively, a description of the study arms was provided.

CONCLUSION

There is a need for revisiting the concept of equipoise and its suggested alternatives for its ethical essence while addressing related challenges.

Patient Reported Outcome and Quality of Life After Delayed Breast Reconstruction - An RCT Comparing Different Reconstructive Methods in Radiated and Non-radiated Patients

BACKGROUND

Health-related quality of life (HRQoL) is one of the core outcomes for breast reconstruction. The aim of this study was to evaluate whether the method of delayed breast reconstruction affects long-term HRQoL.

METHODS

Participants were divided into 2 arms depending on previous radiotherapy, and subsequently randomized between 2 methods of breast reconstruction: a latissimus dorsi flap or a deep inferior epigastric artery perforator flap in the radiated arm and a thoracodorsal flap and implant or an expander in the non-radiated arm. Validated HRQoL instruments were used: BREAST-Q to evaluate breast specific HRQoL and satisfaction, RAND-36 and EQ-5D to evaluate generic HRQoL, and BDI-21 to measure symptoms of depression and anxiety.

RESULTS

During the recruitment period (2009-2015), 233 patients were randomized. After opt-outs and exclusions, the remaining 107 participants comprise the study sample. Postoperative HrQoL was measured on average 7to 8years post-operatively. Response rates varied between 60 and 82 per cent. The BREAST-Q scores were higher after the reconstruction than before for the great majority of domains in both arms; albeit statistically significant only between the 2 methods for physical well-being chest in the radiated arm. Most participants in both arms had minimal or mild depression both before and after the operation.

CONCLUSION

No distinct differences in long-term HrQoL could be seen for different methods There was a clear improvement in HrQoL compared to pre-reconstruction in all groups, but the effect of specific reconstructive methods on scores could not be reliably demonstrated.

The Randomised Controlled Trial at the Intersection of Research Ethics and Innovation

The randomised controlled trial (RCT) has been considered for a long time as the gold standard for evidence generation to support regulatory decision making for medicines. The randomisation procedure involves an ethical dilemma since it means leaving the treatment choice to chance. Although currently contested, the ethical justification for the RCT that has gained widespread acceptance is the notion of ‘clinical equipoise’. This state exists when “there is no consensus within the expert clinical community about the comparative merits of the alternatives to be tested”; it is argued that this confers the ethical grounds for the conduct of an RCT. The prominent position of the RCT is being challenged by new therapeutic modalities for which this study design may be unsuitable. Moreover, alternative approaches to evidence generation represent another area where innovation may have implications for the relevance of the RCT. Against the backdrop of the debate around the equipoise principle and some recent therapeutic and data analytical innovations, the aim of this article is to explore the current standing of the RCT from a regulatory perspective.

IDENTIFICATION OF THRESHOLD FOR LARGE (DRAMATIC) EFFECTS THAT WOULD OBVIATE RANDOMIZED TRIALS IS NOT POSSIBLE

OBJECTIVE

To analyze distribution of "dramatic", large treatment effects.

STUDY DESIGN & SETTING

Pareto distribution modeling of previously reported cohorts of 3,486 randomized trials (RCTs) that enrolled 1,532,459 patients and 730 non-randomized studies (NRS) enrolling 1,650,658 patients.

RESULTS

We calculated the Pareto α parameter, which determines the tail of the distribution for various starting points of distribution [odds ratio_min (OR_min)]. In default analysis using all data at OR_min ≥1, Pareto distribution fit well to the treatment effects of RCTs favoring the new treatments (P = 0.21, Kolmogorov-Smirnov test) with best α = 2.32. For NRS, Pareto fit for OR_min ≥2 with best α = 1.91. For RCTs, theoretical 99th percentile OR was 32.7. The actual 99th percentile OR was 25; which converted into relative risk (RR) = 7.1. The maximum observed effect size was OR = 121 (RR = 11.45). For NRS, theoretical 99th percentile was OR = 315. The actual 99th percentile OR was 294 (RR = 13). The maximum observed effect size was OR = 1473 (RR = 66).

CONCLUSIONS

The effects sizes observed in RCTs and NRS considerably overlap. Large effects are rare and there is no clear threshold for dramatic effects that would obviate future RCTs.

Response adaptive designs for Phase II trials with binary endpoint based on context-dependent information measures

In many rare disease Phase II clinical trials, two objectives are of interest to an investigator: maximising the statistical power and maximising the number of patients responding to the treatment. These two objectives are competing, therefore, clinical trial designs offering a balance between them are needed. Recently, it was argued that response-adaptive designs such as families of multi-arm bandit (MAB) methods could provide the means for achieving this balance. Furthermore, response-adaptive designs based on a concept of context-dependent (weighted) information criteria were recently proposed with a focus on Shannon's differential entropy. The information-theoretic designs based on the weighted Renyi, Tsallis and Fisher informations are also proposed. Due to built-in parameters of these novel designs, the balance between the statistical power and the number of patients that respond to the treatment can be tuned explicitly. The asymptotic properties of these measures are studied in order to construct intuitive criteria for arm selection. A comprehensive simulation study shows that using the exact criteria over asymptotic ones or using information measures with more parameters, namely Renyi and Tsallis entropies, brings no sufficient gain in terms of the power or proportion of patients allocated to superior treatments. The proposed designs based on information-theoretical criteria are compared to several alternative approaches. For example, via tuning of the built-in parameter, one can find designs with power comparable to the fixed equal randomisation's but a greater number of patients responded in the trials.

Dual Uncertainties: On Equipoise, Sex Differences and Chirality in Clinical Research

Ethical justification for clinical research may invoke equipoise, an element of scientific uncertainty regarding the superior choice if presented with different therapeutic options. Given a relative lack of scientific knowledge available for females related to historic tendencies for research to focus predominantly on males, clinical equipoise alone when applied to the context of sex differences may not be sufficient for us to appreciate whether or how a therapy might vary in its effects depending upon participant sex. I explore the analogy of chirality or 'handedness,' arguing we might think of the two sexes as possessing this property: female and male are equally human, yet knowledge of the biology of one sex cannot be completely superimposed onto the other. I propose the concept of chiral equipoise, suggesting that in ethical deliberations around clinical research we consider not only the uncertainty between therapeutic options, but also ask: for which sex?

Perceived barriers to randomised controlled trials in breast reconstruction: obstacle to trial initiation or opportunity to resolve? A qualitative study

BACKGROUND

Implant-based breast reconstruction (IBBR) is the most commonly performed breast reconstruction technique worldwide but the technique is evolving rapidly. High-quality evidence is needed to support practice. Randomised controlled trials (RCTs) provide the best evidence but can be challenging to conduct. iBRA is a four-phased study which aimed to inform the feasibility, design and conduct of an RCT in IBBR. In phase 3, the randomisation acceptability study, an electronic survey and qualitative interviews were conducted to explore professionals' perceptions of future trials in IBBR. Findings from the interviews are presented here.

METHODS

Semi-structured qualitative interviews were undertaken with a purposive sample of 31 health professionals (HPs) who completed the survey to explore their attitudes to the feasibility of potential RCTs in more detail. All interviews were transcribed verbatim and data were analysed thematically using constant comparative techniques. Sampling, data collection and analysis were undertaken iteratively and concurrently until data saturation was achieved.

RESULTS

Almost all HPs acknowledged the need for better evidence to support the practice of IBBR and most identified RCTs as generating the highest-quality evidence. Despite highlighting potential challenges, most participants supported the need for an RCT in IBBR. A minority, however, were strongly opposed to a future trial. The opposition and challenges identified centred around three key themes; (i) limited understanding of pragmatic study design and the value of randomisation in minimising bias; (ii) clinician and patient equipoise and (iii) aspects of surgical culture and training that were not supportive of RCTs.

CONCLUSION

There is a need for well-designed, large-scale RCTs to support the current practice of IBBR but barriers to their acceptability are evident. The perceived barriers to RCTs in breast reconstruction identified in this study are not insurmountable and have previously been overcome in other similar surgical trials. This may represent an opportunity, not only to establish the evidence base for IBBR, but also to improve engagement in RCTs in breast surgery in general to ultimately improve outcomes for patients.

TRIAL REGISTRATION

International Standard Randomised Controlled Trial Number ISRCTN37664281.

Benefit, burden, and impact for a cohort of post-approval cancer combination trials

BACKGROUND

After approval, drug developers often pursue trials aimed at extending the uses of a new drug by combining it with other drugs. Little is known about the risk and benefits associated with such research.

METHODS

To establish a historic benchmark of risk and benefit, we searched Medline and Embase for clinical trials testing anti-cancer drugs in combination within 5 years of approval by the Food and Drug Administration of 12 anti-cancer "index" drugs first licensed 2005-2007 inclusive. Risk was assessed based on grade 3 or above drug-related adverse events; benefit was assessed based on efficacy outcomes and advancement of combinations into clinical practice guidelines or approval by the Food and Drug Administration.

RESULTS

We captured 323 published post-approval trials exploring combinations, including 266 unique combination-indication pairings and enrolling 29,835 patients. The pooled risk ratios for treatment-related grade 3-4 severe adverse events and deaths attributed to the study drugs for trials randomized between a combination arm and a comparator were 1.54 (1.33-1.79) and 1.51 (1.16-1.97), respectively. The pooled hazard ratios for overall survival and progression-free survival were 0.99 (0.92-1.05) and 0.85 (0.79-0.93), respectively. None of the combination-indication pairings launched after initial drug approval received approval by the Food and Drug Administration, and 13 pairings (4.9%) were recommended by the National Comprehensive Cancer Network within 5 years of the first trial within that pairing. The proportion of patients in our sample who participated in trials leading to an approval by the Food and Drug Administration or a National Comprehensive Cancer Network guideline recommendation was 12.7% with 5 years of follow-up, and 22.3% among pairings for which there were 8 years of follow-up.

CONCLUSION

Patients were just as likely to benefit in the treatment arm as the control arm in terms of overall survival, but they were more likely to experience a treatment-related severe adverse event in post-approval trials of combination therapy.

Factors associated with trial recruitment, preferences, and treatments received were elucidated in a comprehensive cohort study

OBJECTIVES

Recruitment to pragmatic trials is often difficult, and little is known about factors associated with key participation and treatment decisions. These were explored in the Prostate cancer testing and Treatment (ProtecT) study.

STUDY DESIGN AND SETTING

Baseline sociodemographic, patient-reported outcome, clinical history, and prostate cancer biopsy data were collected for all patients eligible to take part in the ProtecT trial, in a comprehensive cohort design. Men who rejected randomization specified a preferred option and were followed up identically to the randomized cohort. Factors associated with participation decisions, patient preferences, and reasons for changing treatment were explored.

RESULTS

Of 2,664 men with clinically localized prostate cancer, 997 (37%) rejected randomization. Their treatment preferences and subsequent treatment choices/changes in both randomized and treatment choice cohorts were strongly associated with prostate cancer risk features: toward active monitoring for low-risk disease and toward radical options with higher risk prostate cancer. Among many factors measured, only a small number of weak associations were found for occupation groups and some patient symptoms. Similar percentages changed from the random allocation and initially stated preference.

CONCLUSION

The comprehensive cohort design provided new insights into trial recruitment and participation decisions. Opportunities to improve recruitment by supporting recruiters with equipoise and patient preferences were identified.

The Scientific Impact of Positive and Negative Phase 3 Cancer Clinical Trials

IMPORTANCE

Positive phase 3 cancer clinical trials are widely hailed, while trials with negative results are often interpreted as scientific failures. We hypothesized that these interpretations would be reflected in the scientific literature.

OBJECTIVE

To compare the scientific impact of positive vs negative phase 3 cancer clinical treatment trials.

DESIGN, SETTING, AND PARTICIPANTS

We examined the phase 3 trial history of SWOG, a national cancer clinical trials consortium, over a 30-year period (1985-2014). Scientific impact was assessed according to multiple publication and citation outcomes. Citation data were obtained using Google Scholar. Citation counts were compared using generalized estimating equations for Poisson regression. Any trial that was formally evaluated for the randomized treatment comparison was included for analysis of publication and citation outcomes. Trials were categorized as positive if they achieved a statistically significant result in favor of the new experimental treatment for the protocol-specified primary end point. Trials were categorized as negative if they achieved a statistically significant result in favor of standard therapy or a null result with no statistically significant benefit for either the experimental or standard therapy.

MAIN OUTCOMES AND MEASURES

Impact factors for the journals publishing the primary trial results, and the number of citations for the primary trial articles and all secondary articles associated with the trials.

RESULTS

Ninety-four studies enrolling n = 46 424 patients were analyzed. Twenty-eight percent of trials were positive (26 of 94). The primary publications from positive trials were published in journals with higher mean (SD) 2-year impact factors (28 [19] vs 18 [13]; P = .007) and were cited twice as often as negative trials (mean per year, 43 vs 21; relative risk, 2.0; 95% CI, 1.1-3.9; P = .03). However, the number of citations from all primary and secondary articles did not significantly differ between positive and negative trials (mean per year, 55 vs 45; relative risk, 1.2; 95% CI, 0.7-2.3; P = .53).

CONCLUSIONS AND RELEVANCE

The scientific impact of the primary articles from positive phase 3 randomized cancer clinical trials was twice as great as for negative trials. But when all of the articles associated with the trials were considered, the scientific impact between positive and negative trials was similar. Positive trials indicate clinical advances, but negative trials also have a sizeable scientific impact by generating important scientific observations and new hypotheses and by showing what new treatments should not be used.

Mechanisms and direction of allocation bias in randomised clinical trials

BACKGROUND

Selective allocation of patients into the compared groups of a randomised trial may cause allocation bias, but the mechanisms behind the bias and its directionality are incompletely understood. We therefore analysed the mechanisms and directionality of allocation bias in randomised clinical trials.

METHODS

Two systematic reviews and a theoretical analysis. We conducted one systematic review of empirical studies of motives/methods for deciphering patient allocation sequences; and another review of methods publications commenting on allocation bias. We theoretically analysed the mechanisms of allocation bias and hypothesised which main factors predicts its direction.

RESULTS

Three empirical studies addressed motives/methods for deciphering allocation sequences. Main motives included ensuring best care for patients and ensuring best outcome for the trial. Main methods included various manipulations with randomisation envelopes. Out of 57 methods publications 11 (19 %) mentioned explicitly that allocation bias can go in either direction. We hypothesised that the direction of allocation bias is mainly decided by the interaction between the patient allocators' motives and treatment preference.

CONCLUSION

Inadequate allocation concealment may exaggerate treatment effects in some trials while underestimate effects in others. Our hypothesis provides a theoretical overview of the main factors responsible for the direction of allocation bias.

Conveying Equipoise during Recruitment for Clinical Trials: Qualitative Synthesis of Clinicians' Practices across Six Randomised Controlled Trials

BACKGROUND

Randomised controlled trials (RCTs) are essential for evidence-based medicine and increasingly rely on front-line clinicians to recruit eligible patients. Clinicians' difficulties with negotiating equipoise is assumed to undermine recruitment, although these issues have not yet been empirically investigated in the context of observable events. We aimed to investigate how clinicians conveyed equipoise during RCT recruitment appointments across six RCTs, with a view to (i) identifying practices that supported or hindered equipoise communication and (ii) exploring how clinicians' reported intentions compared with their actual practices.

METHODS AND FINDINGS

Six pragmatic UK-based RCTs were purposefully selected to include several clinical specialties (e.g., oncology, surgery) and types of treatment comparison. The RCTs were all based in secondary-care hospitals (n = 16) around the UK. Clinicians recruiting to the RCTs were interviewed (n = 23) to understand their individual sense of equipoise about the RCT treatments and their intentions for communicating equipoise to patients. Appointments in which these clinicians presented the RCT to trial-eligible patients were audio-recorded (n = 105). The appointments were analysed using thematic and content analysis approaches to identify practices that supported or challenged equipoise communication. A sample of appointments was independently coded by three researchers to optimise reliability in reported findings. Clinicians and patients provided full written consent to be interviewed and have appointments audio-recorded. Interviews revealed that clinicians' sense of equipoise varied: although all were uncertain about which trial treatment was optimal, they expressed different levels of uncertainty, ranging from complete ambivalence to clear beliefs that one treatment was superior. Irrespective of their personal views, all clinicians intended to set their personal biases aside to convey trial treatments neutrally to patients (in accordance with existing evidence). However, equipoise was omitted or compromised in 48/105 (46%) of the recorded appointments. Three commonly recurring practices compromised equipoise communication across the RCTs, irrespective of clinical context. First, equipoise was overridden by clinicians offering treatment recommendations when patients appeared unsure how to proceed or when they asked for the clinician's expert advice. Second, clinicians contradicted equipoise by presenting imbalanced descriptions of trial treatments that conflicted with scientific information stated in the RCT protocols. Third, equipoise was undermined by clinicians disclosing their personal opinions or predictions about trial outcomes, based on their intuition and experience. These broad practices were particularly demonstrated by clinicians who had indicated in interviews that they held less balanced views about trial treatments. A limitation of the study was that clinicians volunteering to take part in the research might have had a particular interest in improving their communication skills. However, the frequency of occurrence of equipoise issues across the RCTs suggests that the findings are likely to be reflective of clinical recruiters' practices more widely.

CONCLUSIONS

Communicating equipoise is a challenging process that is easily disrupted. Clinicians' personal views about trial treatments encroached on their ability to convey equipoise to patients. Clinicians should be encouraged to reflect on personal biases and be mindful of the common ways in which these can arise in their discussions with patients. Common pitfalls that recurred irrespective of RCT context indicate opportunities for specific training in communication skills that would be broadly applicable to a wide clinical audience.

Control treatments in biologics trials of rheumatoid arthritis were often not deemed acceptable in the context of care

OBJECTIVES

Control treatments in randomized controlled trials (RCTs) should not deliberately disadvantage patients. The objectives of the study were to compare (1) willingness to include vs. (2) willingness to prescribe control treatment among physicians randomized to assess, respectively, either (1) enrollment in a trial or (2) appropriateness of control treatment in a care context for the same fictional patient.

STUDY DESIGN AND SETTING

Physicians were authors of articles about rheumatoid arthritis (RA), involved in RA patient care, and used to enrolling patients in trials. The outcomes were willingness to give control treatment: trial enrollment or control-treatment appropriateness in care context. We derived three case vignettes of fictional standard eligible patients for each of 30 RCTs assessing biologics in RA. Physicians were randomly allocated to the "trial" or "care" arm. For each of the 90 fictional patients, physicians assigned to the trial arm were asked if they would enroll the patient in the RCT the patient was derived from. For the same 90 fictional patients, physicians assigned to the care arm were asked if the control treatment of the RCT was appropriate in a context of usual care.

RESULTS

Of the 1,779 physicians invited to participate, 151 were randomized. Half of the fictional patients {41/90; 45% [95% confidence interval (CI): 37%, 53%]} would be enrolled in the RCT although the control-arm treatment of the RCT was not considered appropriate for them in the context of care. This rate differed by type of comparator [55% for non-head-to-head RCTs vs. 6% for head-to-head RCTs; adjusted odds ratio (aOR), 23.9 (95% CI: 5.5, 92.7)] and duration of trial control treatment [56% for ≤24 weeks and 15% for >24 weeks; aOR, 10.7 (95% CI: 2.8, 63.9)] but not patient RA activity [aOR, 2.5 (95% CI: 1.0, 6.6)]. The limitation of this study was that physicians gave their opinion on fictional patients with only RA.

CONCLUSIONS

Control treatments in RCTs of biologics in RA are often deemed not acceptable in the context of usual care, especially those for non-head-to-head RCTs. These findings raise ethical concerns and challenge the choice of the comparator in RCTs.

[Variability in decision-making for treatment choice of intracranial aneurysms]

OBJECTIVES

To measure the variability in choosing treatment options in different clinical situations involving intracranial aneurysms.

MATERIALS AND METHODS

A questionnaire regarding 25 clinical cases was presented via visual projection, to attendees of the Congrès de la Société française de neurochirurgie et de la Société de langue française de neurochirurgie held in Toulouse from May 9th to May 12th, 2012. The audience (n=59) consisted of 58 neurosurgeons and one neuroradiologist. A minority of them (29.2%) stated that they specialized in vascular neurosurgery. The questionnaire dealt with 25 illustrative clinical cases, in which age, gender, and clinical context were provided along with the corresponding angiographic image of the aneurysm. The questionnaire asked whether the physician would have proposed treatment, and if so, which type of treatment (clip, coil or other). In addition, the physician had to indicate, on a scale of one to ten, the degree of confidence they had in their decision.

RESULTS

For one-third of the cases, there was at least 10% of the respondents who opted for a decision opposite to the one of the majority. For 41.7% of the cases, the proportion of respondents who opted for the clip was not significantly different from the proportion of those who opted for the coil.

CONCLUSION

Even in a relatively homogenous group of physicians, there were significantly diverging opinions regarding the management of cerebral aneurysms. This demonstrates the need for evidence-based data from controlled randomized studies.

Treatment success in cancer: industry compared to publicly sponsored randomized controlled trials

OBJECTIVE

To assess if commercially sponsored trials are associated with higher success rates than publicly-sponsored trials.

STUDY DESIGN AND SETTINGS

We undertook a systematic review of all consecutive, published and unpublished phase III cancer randomized controlled trials (RCTs) conducted by GlaxoSmithKline (GSK) and the NCIC Clinical Trials Group (CTG). We included all phase III cancer RCTs assessing treatment superiority from 1980 to 2010. Three metrics were assessed to determine treatment successes: (1) the proportion of statistically significant trials favouring the experimental treatment, (2) the proportion of the trials in which new treatments were considered superior according to the investigators, and (3) quantitative synthesis of data for primary outcomes as defined in each trial.

RESULTS

GSK conducted 40 cancer RCTs accruing 19,889 patients and CTG conducted 77 trials enrolling 33,260 patients. 42% (99%CI 24 to 60) of the results were statistically significant favouring experimental treatments in GSK compared to 25% (99%CI 13 to 37) in the CTG cohort (RR = 1.68; p = 0.04). Investigators concluded that new treatments were superior to standard treatments in 80% of GSK compared to 44% of CTG trials (RR = 1.81; p<0.001). Meta-analysis of the primary outcome indicated larger effects in GSK trials (odds ratio = 0.61 [99%CI 0.47-0.78] compared to 0.86 [0.74-1.00]; p = 0.003). However, testing for the effect of treatment over time indicated that treatment success has become comparable in the last decade.

CONCLUSIONS

While overall industry sponsorship is associated with higher success rates than publicly-sponsored trials, the difference seems to have disappeared over time.

New treatments compared to established treatments in randomized trials

BACKGROUND

The proportion of proposed new treatments that are 'successful' is of ethical, scientific, and public importance. We investigated how often new, experimental treatments evaluated in randomized controlled trials (RCTs) are superior to established treatments.

OBJECTIVES

Our main question was: "On average how often are new treatments more effective, equally effective or less effective than established treatments?" Additionally, we wanted to explain the observed results, i.e. whether the observed distribution of outcomes is consistent with the 'uncertainty requirement' for enrollment in RCTs. We also investigated the effect of choice of comparator (active versus no treatment/placebo) on the observed results.

SEARCH METHODS

We searched the Cochrane Methodology Register (CMR) 2010, Issue 1 in The Cochrane Library (searched 31 March 2010); MEDLINE Ovid 1950 to March Week 2 2010 (searched 24 March 2010); and EMBASE Ovid 1980 to 2010 Week 11 (searched 24 March 2010).

SELECTION CRITERIA

Cohorts of studies were eligible for the analysis if they met all of the following criteria: (i) consecutive series of RCTs, (ii) registered at or before study onset, and (iii) compared new against established treatments in humans.

DATA COLLECTION AND ANALYSIS

RCTs from four cohorts of RCTs met all inclusion criteria and provided data from 743 RCTs involving 297,744 patients. All four cohorts consisted of publicly funded trials. Two cohorts involved evaluations of new treatments in cancer, one in neurological disorders, and one for mixed types of diseases. We employed kernel density estimation, meta-analysis and meta-regression to assess the probability of new treatments being superior to established treatments in their effect on primary outcomes and overall survival.

MAIN RESULTS

The distribution of effects seen was generally symmetrical in the size of difference between new versus established treatments. Meta-analytic pooling indicated that, on average, new treatments were slightly more favorable both in terms of their effect on reducing the primary outcomes (hazard ratio (HR)/odds ratio (OR) 0.91, 99% confidence interval (CI) 0.88 to 0.95) and improving overall survival (HR 0.95, 99% CI 0.92 to 0.98). No heterogeneity was observed in the analysis based on primary outcomes or overall survival (I(2) = 0%). Kernel density analysis was consistent with the meta-analysis, but showed a fairly symmetrical distribution of new versus established treatments indicating unpredictability in the results. This was consistent with the interpretation that new treatments are only slightly superior to established treatments when tested in RCTs. Additionally, meta-regression demonstrated that results have remained stable over time and that the success rate of new treatments has not changed over the last half century of clinical trials. The results were not significantly affected by the choice of comparator (active versus placebo/no therapy).

AUTHORS' CONCLUSIONS

Society can expect that slightly more than half of new experimental treatments will prove to be better than established treatments when tested in RCTs, but few will be substantially better. This is an important finding for patients (as they contemplate participation in RCTs), researchers (as they plan design of the new trials), and funders (as they assess the 'return on investment'). Although we provide the current best evidence on the question of expected 'success rate' of new versus established treatments consistent with a priori theoretical predictions reflective of 'uncertainty or equipoise hypothesis', it should be noted that our sample represents less than 1% of all available randomized trials; therefore, one should exercise the appropriate caution in interpretation of our findings. In addition, our conclusion applies to publicly funded trials only, as we did not include studies funded by commercial sponsors in our analysis.

When is it rational to participate in a clinical trial? A game theory approach incorporating trust, regret and guilt

BACKGROUND

Randomized controlled trials (RCTs) remain an indispensable form of human experimentation as a vehicle for discovery of new treatments. However, since their inception RCTs have raised ethical concerns. The ethical tension has revolved around "duties to individuals" vs. "societal value" of RCTs. By asking current patients "to sacrifice for the benefit of future patients" we risk subjugating our duties to patients' best interest to the utilitarian goal for the good of others. This tension creates a key dilemma: when is it rational, from the perspective of the trial patients and researchers (as societal representatives of future patients), to enroll in RCTs?

METHODS

We employed the trust version of the prisoner's dilemma since interaction between the patient and researcher in the setting of a clinical trial is inherently based on trust. We also took into account that the patient may have regretted his/her decision to participate in the trial, while a researcher may feel guilty because he/she abused the patient's trust.

RESULTS

We found that under typical circumstances of clinical research, most patients can be expected not to trust researchers, and most researchers can be expected to abuse the patients' trust. The most significant factor determining trust was the success of experimental or standard treatments, respectively. The more that a researcher believes the experimental treatment will be successful, the more incentive the researcher has to abuse trust. The analysis was sensitive to the assumptions about the utilities related to success and failure of therapies that are tested in RCTs. By varying all variables in the Monte Carlo analysis we found that, on average, the researcher can be expected to honor a patient's trust 41% of the time, while the patient is inclined to trust the researcher 69% of the time. Under assumptions of our model, enrollment into RCTs represents a rational strategy that can meet both patients' and researchers' interests simultaneously 19% of the time.

CONCLUSIONS

There is an inherent ethical dilemma in the conduct of RCTs. The factors that hamper full co-operation between patients and researchers in the conduct of RCTs can be best addressed by: a) having more reliable estimates on the probabilities that new vs. established treatments will be successful, b) improving transparency in the clinical trial system to ensure fulfillment of "the social contract" between patients and researchers.

Uncertainty and equipoise: at interplay between epistemology, decision making and ethics

In recent years, various authors have proposed that the concept of equipoise be abandoned because it conflates the practice of clinical care with clinical research. At the same time, the equipoise opponents acknowledge the necessity of clinical research if there are unresolved uncertainties about the effects of proposed healthcare interventions. As equipoise represents just 1 measure of uncertainty, proposals to abandon equipoise while maintaining a requirement for addressing uncertainties are contradictory and ultimately not valid. As acknowledgment and articulation of uncertainties represent key scientific and moral requirements for human experimentation, the concept of equipoise remains the most useful framework to link the theory of human experimentation with the theory of rational choice. In this article, I show how uncertainty (equipoise) is at the intersection between epistemology, decision making and ethics of clinical research. In particular, I show how our formulation of responses to uncertainties of hoped-for benefits and unknown harms of testing is a function of the way humans cognitively process information. This approach is based on the view that considerations of ethics and rationality cannot be separated. I analyze the response to uncertainties as it relates to the dual-processing theory, which postulates that rational approach to (clinical research) decision making depends both on analytical, deliberative processes embodied in scientific method (system II), and good human intuition (system I). Ultimately, our choices can only become wiser if we understand a close and intertwined relationship between irreducible uncertainty, inevitable errors and unavoidable injustice.

Randomised clinical trials in surgery: a look at the ethical and practical issues

An ethically conducted randomised controlled trial (RCT) is the backbone of evidence based medicine. In surgical practice however, RCTs have taken a backseat, drawing much adverse comment. There are several reasons to explain surgeons' disinclination to conduct RCTs. These include many practical difficulties such as the problem of blinding surgical procedures, design and funding issues. There are also many ethical issues which need to be considered including the concept of equipoise as well as the ethical issues associated with sham surgery as a control. While there is no doubt that RCTs are essential and in fact have helped to weed out several unnecessary surgical procedures, it is important not to lose sight of the fact that they may not be always necessary in order to obtain evidence in favour of a procedure. Possible solutions could be to follow guidelines that have been issued by learned bodies and a strict adherence to all ethical norms that have been recommended in the conduct of trials.

Treatment success in pragmatic randomised controlled trials: a review of trials funded by the UK Health Technology Assessment programme

BACKGROUND

Previous research reviewed treatment success and whether the collective uncertainty principle is met in RCTs in the US National Cancer Institute portfolio. This paper classifies clinical trials funded by the UK HTA programme by results using the method applied to the US Cancer Institute trials, and compares the two portfolios.

METHODS

Data on all completed randomised controlled trials funded by the HTA programme 1993-2008 were extracted. Each trial's primary results was classified into six categories; 1) statistically significant in favour of the new treatment, 2) statistically significant in favour of the control treatment 3) true negative, 4) truly inconclusive, 5) inconclusive in favour of new treatment or 6) inconclusive in favour of control treatment. Trials were classified by comparing the 95% confidence interval for the difference in primary outcome to the difference specified in the sample size calculation. The results were compared with Djulbegovic's analysis of NCI trials.

RESULTS

Data from 51 superiority trials were included, involving over 48,000 participants and a range of diseases and interventions. 85 primary comparisons were available because some trials had more than two randomised arms or had several primary outcomes. The new treatment had superior results (whether significant or not) in 61% of the comparisons (52/85 95% CI 49.9% to 71.6%). The results were conclusive in 46% of the comparisons (19% statistically significant in favour of the new treatment, 5% statistically significant in favour of the control and 22% true negative). The results were classified as truly inconclusive (i.e. failed to answer the question asked) for 24% of comparisons (20/85). HTA trials included fewer truly inconclusive and statistically significant results and more results rated as true negative than NCI trials.

CONCLUSIONS

The pattern of results in HTA trials is similar to that of the National Cancer Institute portfolio. Differences that existed were plausible given the differences in the types of trials -HTA trials are more pragmatic. The results indicate HTA trials are compatible with equipoise. This classification usefully summarises the results from clinical trials and enables comparisons of different portfolios of trials.

A social network analysis of treatment discoveries in cancer

Controlled clinical trials are widely considered to be the vehicle to treatment discovery in cancer that leads to significant improvements in health outcomes including an increase in life expectancy. We have previously shown that the pattern of therapeutic discovery in randomized controlled trials (RCTs) can be described by a power law distribution. However, the mechanism generating this pattern is unknown. Here, we propose an explanation in terms of the social relations between researchers in RCTs. We use social network analysis to study the impact of interactions between RCTs on treatment success. Our dataset consists of 280 phase III RCTs conducted by the NCI from 1955 to 2006. The RCT networks are formed through trial interactions formed i) at random, ii) based on common characteristics, or iii) based on treatment success. We analyze treatment success in terms of survival hazard ratio as a function of the network structures. Our results show that the discovery process displays power law if there are preferential interactions between trials that may stem from researchers' tendency to interact selectively with established and successful peers. Furthermore, the RCT networks are “small worlds”: trials are connected through a small number of ties, yet there is much clustering among subsets of trials. We also find that treatment success (improved survival) is proportional to the network centrality measures of closeness and betweenness. Negative correlation exists between survival and the extent to which trials operate within a limited scope of information. Finally, the trials testing curative treatments in solid tumors showed the highest centrality and the most influential group was the ECOG. We conclude that the chances of discovering life-saving treatments are directly related to the richness of social interactions between researchers inherent in a preferential interaction model.

Personalized diagnostics: the struggle for position

For several major cancers, drug selection already pivots on biomarker results (e.g., trastuzumab for breast cancer, and gefitinib and erlotinib for lung cancer). Fast-paced advances in genomic and proteomic laboratory technologies could enable the widespread use of molecular testing before therapy selection in any field of medicine. This article describes two potentially large obstructions to such innovation. First, laboratory tests have traditionally been commodities with low prices, prices that matched the resources required to operate the laboratory technology itself. Assuming that the marginal costs of molecular laboratory technology will fall, there will be a widening chasm between estimated test revenue and the costs of innovative and definitive clinical trials, and regulatory approval for new tests. Without corrective action, even cost-saving laboratory tests could be in shortfall, because they will not be created through upfront investment. Second, it is argued that while diagnostic tests, drugs and surgical procedures should meet a fundamental standard for payer coverage (‘will health outcomes be improved?’), molecular diagnostics could require different analysis pathways than those that are used to evaluate interventions.

Conducting research in the aftermath of disasters: ethical considerations

Disaster research focuses on the impact disasters have on people and social structures. Planning for and responding to disasters require evidence to guide decision-makers. The need for such evidence provides an ethical mandate for the conduct of sound disaster research. Disaster research ethics draws attention to ethical issues common to all research involving human subjects. However, disaster research involves a number of distinctive factors, including the degree of devastation affecting participants and the urgency often involved in initiating research projects. Such factors generate ethical issues not usually encountered with other types of research, and create tensions that must be taken into account in designing and conducting disaster research so that it attains the highest ethical standards. An overview of general research ethics issues is presented here in the context of disaster research. As with all research involving humans, protection of participants and minimizing harm is the highest ethical priority. Other ethical issues include formal ethical approval, informed consent, balancing burdens and benefits, participant recruitment, coercion, the role of compensation, and conflicts of interest. Using examples from specific studies, some of the distinctive features of disaster research ethics are discussed. These include cross-cultural collaboration and communication, vulnerability of participants arising from the degree of devastation, avoiding exploitation of disaster victims, and protecting researchers. The article concludes with some of the major challenges facing disaster research ethics and how they might be addressed.