The ethics of ‘Trials within Cohorts’ (TwiCs): 2nd international symposium
Bibliographic record
Abstract
On 7-8 th November 2016, 60 people with an interest in the 'Trials within Cohorts' (TwiCs) approach for randomised controlled trial design met in London.The purpose of this 2 nd TwiCs international symposium was to share perspectives and experiences on ethical aspects of the TwiCs design, discuss how TwiCs relate to the current ethical framework, provide a forum in which to discuss and debate ethical issues and identify future directions for conceptual and empirical research.The symposium was supported by the Wellcome Trust and the NIHR CLAHRC Yorkshire and Humber and organised by members of the TwiCs network led by Clare Relton and attended by people from the UK, the Netherlands, Norway, Canada and USA.The two-day symposium enabled an international group to meet and share experiences of the TwiCs design (also known as the 'cohort multiple RCT design'), and to discuss plans for future research.Over the two days, invited plenary talks were interspersed by discussions, posters and mini presentations from bioethicists, triallists and health research regulators.Key findings of the symposium were: (1) It is possible to make a compelling case to ethics committees that TwiCs designs are appropriate and ethical; (2) The importance of wider considerations around the ethics of inefficient trial designs; and (3) some questions about the ethical requirements for content and timing of informed consent for a study using the TwiCs design need to be decided on a case-by-case basis. Main reportOn 7-8 th November 2016, 60 people with an interest in the 'Trials within Cohorts' (TwiCs) design met in London for the 2 nd TwiCs international symposium.The symposium was supported by the Wellcome Trust and NIHR CLAHRC Yorkshire and Humber and organised by members of the TwiCs network led by Clare Relton.As well as UK participants, people came from the Netherlands, Norway, Canada and USA.Over the two days, the invited plenary talks were interspersed by discussions, posters and mini presentations from bioethicists, triallists and health research regulators.On the first day (7 th November, 2016), Jon Nicholl (University of Sheffield, UK) opened the meeting, welcoming all to the symposium.He described how the first international symposium in 2014 brought together triallists using the design for the first time, and led to this, the 2 nd symposium which aimed to provide a forum in which to discuss and debate ethical issues including how the TwiCs approach relates to the current ethical framework.What are TwiCs?Clare Relton (University of Sheffield, UK) set the scene by outlining the Trials within Cohorts (TwiCs) approach as described in the original article (Fig. 1) in the BMJ in 2010 [1], and the 7 key features of the design: (I) Recruitment of a large observational cohort of patients/ people with the condition of interest (II) Regular measurement of outcomes for the whole cohort (III) Capacity for multiple randomised controlled trials over time.Then for each randomised controlled trial: (IV) Identification of all eligible people in the cohort (V) Random selection of some individuals from all eligible people in the cohort, who are then offered the trial intervention (VI) Comparison of the outcomes in randomly selected people with the outcomes in eligible people not randomly selected; that is, those receiving usual care (VII) "Patient centred" informed consent; that is, the process of obtaining information and consent aims to replicate that in routine health care as far as is possible.Ethics in current use Clare described how more than 20 studies using the TwiCs design now had ethics board approval from boards in Australia, Canada, Finland, France, Germany, Mexico, Netherlands, Spain, UK, and the USA.These studies were recruiting cohort populations (e.g.early life, children and adolescents, young indigenous, adults, older people) in a variety of settings (e.g., hospital, primary care), in order to facilitate trials in diverse health areas (e.g., attention deficit hyperactivity disorder, breast cancer, colo-rectal cancer, bone metastases, depression, hepatitis C, HIV, hip fracture, falls prevention, long term conditions, severe mental illness, scleroderma).Embedded within these cohorts, there were at least 20 randomised trials testing a wide range of interventions, and various approaches to informed consent were being used in these studies.Jon Nicholl (University of Sheffield, UK) then gave an example of an emergency medicine research study where it was not possible to obtain informed consent prior to randomisation and have a viable trial, which illustrated that informed consent for participation in a trial is not always required.Jon argued that although all trial participants in TwiCs should receive information about data collection, storage and sharing and all other non-therapeutic research processes, only those in the intervention group need to receive information about the intervention.TwiCs designs randomly select from the cohort and offer the intervention being tested, those unselected are not actually allocated to 'treatment as usual' , so there is no ethical obligation to tell those unselected about those who were selected, or about
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How this classification was reachedexpand
Full frame machine prediction
Teacher imitationNot calibrated prevalence, not ground truth. Human validation pending. The Gemma side is a direct model label for every work in the frame, read from the title-only record. The Codex side is a classifier learned from the 10,348 direct Codex labels and calibrated to design-weighted sample rates; fields without enough sample support carry no Codex call. Candidate is the union of the two sides; consensus is their intersection. These outputs are machine_predicted_unvalidated and are not human labels.
Distilled classifier scores by category (both heads)
| Category | Codex | Gemma |
|---|---|---|
| Metaresearch | 0.535 | 0.534 |
| Meta-epidemiology (narrow) | 0.001 | 0.002 |
| Meta-epidemiology (broad) | 0.003 | 0.002 |
| Bibliometrics | 0.002 | 0.002 |
| Science and technology studies | 0.006 | 0.068 |
| Scholarly communication | 0.020 | 0.018 |
| Open science | 0.005 | 0.011 |
| Research integrity | 0.039 | 0.038 |
| Insufficient payload (model declined to judge) | 0.005 | 0.001 |
Machine scores (provisional)
The two teacher heads of the student model, read on this work. A score orders the frame for review; it never asserts a category, and the validation status ships verbatim with every row.
Baseline scores from an immature model (maturity gate not passed, 7 training rounds). Scores rank; they never assert a category.
score_only:v0-immature-baseline · verbatim from the scoring run: score_only means the number may rank works, and no category label ships from itClassification
machine, unvalidatedMachine predicted; the direct Gemma label and the distilled Codex classifier agree on what is shown here.
How this classification was reached, model by model and score by score, is at the end of the page under "How this classification was reached".