1
|
Hemming K, Copas A, Forbes A, Kasza J. What type of cluster randomized trial for which setting? JOURNAL OF EPIDEMIOLOGY AND POPULATION HEALTH 2024; 72:202195. [PMID: 38477476 DOI: 10.1016/j.jeph.2024.202195] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/16/2023] [Revised: 01/03/2024] [Accepted: 01/08/2024] [Indexed: 03/14/2024]
Abstract
The cluster randomized trial allows a randomized evaluation when it is either not possible to randomize the individual or randomizing individuals would put the trial at high risk of contamination across treatment arms. There are many variations of the cluster randomized design, including the parallel design with or without baseline measures, the cluster randomized cross-over design, the stepped-wedge cluster randomized design, and more recently-developed variants such as the batched stepped-wedge design and the staircase design. Once it has been clearly established that there is a need for cluster randomization, one ever important question is which form the cluster design should take. If a design in which time is split into multiple trial periods is to be adopted (e.g. as in a stepped-wedge), researchers must decide whether the same participants should be measured in multiple trial periods (cohort sampling); or if different participants should be measured in each period (continual recruitment or cross-sectional sampling). Here we outline the different possible options and weigh up the pros and cons of the different design choices, which revolve around statistical efficiency, study logistics and the assumptions required.
Collapse
Affiliation(s)
- Karla Hemming
- Institute of Applied Health Research, University of Birmingham, Birmingham, UK.
| | - Andrew Copas
- MRC Clinical Trials Unit at University College London, London, UK
| | - Andrew Forbes
- School of Public Health and Preventive Medicine, Monash University, Victoria, Australia
| | - Jessica Kasza
- School of Public Health and Preventive Medicine, Monash University, Victoria, Australia
| |
Collapse
|
2
|
Leviton A, Loddenkemper T. Design, implementation, and inferential issues associated with clinical trials that rely on data in electronic medical records: a narrative review. BMC Med Res Methodol 2023; 23:271. [PMID: 37974111 PMCID: PMC10652539 DOI: 10.1186/s12874-023-02102-4] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/17/2022] [Accepted: 11/08/2023] [Indexed: 11/19/2023] Open
Abstract
Real world evidence is now accepted by authorities charged with assessing the benefits and harms of new therapies. Clinical trials based on real world evidence are much less expensive than randomized clinical trials that do not rely on "real world evidence" such as contained in electronic health records (EHR). Consequently, we can expect an increase in the number of reports of these types of trials, which we identify here as 'EHR-sourced trials.' 'In this selected literature review, we discuss the various designs and the ethical issues they raise. EHR-sourced trials have the potential to improve/increase common data elements and other aspects of the EHR and related systems. Caution is advised, however, in drawing causal inferences about the relationships among EHR variables. Nevertheless, we anticipate that EHR-CTs will play a central role in answering research and regulatory questions.
Collapse
Affiliation(s)
- Alan Leviton
- Department of Neurology, Boston Children's Hospital, Harvard Medical School, Boston, MA, USA.
| | - Tobias Loddenkemper
- Department of Neurology, Boston Children's Hospital, Harvard Medical School, Boston, MA, USA
| |
Collapse
|
3
|
MacKay D, Cohn E. Public Policy Experiments without Equipoise: When Is Randomization Fair? Ethics Hum Res 2023; 45:15-28. [PMID: 36691691 DOI: 10.1002/eahr.500153] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/25/2023]
Abstract
Government agencies and nonprofit organizations have increasingly turned to randomized controlled trials (RCTs) to evaluate public policy interventions. Random assignment is widely understood to be fair when there is equipoise; however, some scholars and practitioners argue that random assignment is also permissible when an intervention is reasonably expected to be superior to other trial arms. For example, some argue that random assignment to such an intervention is fair when the intervention is scarce, for it is sometimes fair to use a lottery to allocate scarce goods. We investigate the permissibility of randomization in public policy RCTs when there is no equipoise, identifying two sets of conditions under which it is fair to allocate access to a superior intervention via random assignment. We also reject oft-made claims that alternative study designs, including stepped-wedge designs and uneven randomization, offer fair ways to allocate beneficial interventions.
Collapse
Affiliation(s)
- Douglas MacKay
- Associate professor in the Department of Public Policy at the University of North Carolina at Chapel Hill
| | - Emma Cohn
- Undergraduate student majoring in public policy and global studies at the University of North Carolina at Chapel Hill
| |
Collapse
|
4
|
Hemming K, Proschan MA, Stephens-Shields AJ. Thirteenth annual UPenn conference on statistical issues in clinical trials: Cluster randomized clinical trials-opportunities and challenges (morning panel session). Clin Trials 2022; 19:384-395. [PMID: 35787213 DOI: 10.1177/17407745221101267] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Affiliation(s)
| | - Michael A Proschan
- National Institute of allergy and Infectious Disease, NIH, Bethesda, MD, USA
| | | |
Collapse
|
5
|
Federico CA, Heagerty PJ, Lantos J, O'Rourke P, Rahimzadeh V, Sugarman J, Weinfurt K, Wendler D, Wilfond BS, Magnus D. Ethical and epistemic issues in the design and conduct of pragmatic stepped-wedge cluster randomized clinical trials. Contemp Clin Trials 2022; 115:106703. [PMID: 35176501 PMCID: PMC9272561 DOI: 10.1016/j.cct.2022.106703] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/01/2021] [Revised: 01/27/2022] [Accepted: 02/02/2022] [Indexed: 11/27/2022]
Abstract
Stepped-wedge cluster randomized trial (SW-CRT) designs are increasingly employed in pragmatic research; they differ from traditional parallel cluster randomized trials in which an intervention is delivered to a subset of clusters, but not to all. In a SW-CRT, all clusters receive the intervention under investigation by the end of the study. This approach is thought to avoid ethical concerns about the denial of a desired intervention to participants in control groups. Such concerns have been cited in the literature as a primary motivation for choosing SW-CRT design, however SW-CRTs raise additional ethical concerns related to the delayed implementation of an intervention and consent. Yet, PCT investigators may choose SW-CRT designs simply because they are concerned that other study designs are infeasible. In this paper, we examine justifications for the use of SW-CRT study design, over other designs, by drawing on the experience of the National Institutes of Health's Health Care Systems Research Collaboratory (NIH Collaboratory) with five pragmatic SW-CRTs. We found that decisions to use SW-CRT design were justified by practical and epistemic reasons rather than ethical ones. These include concerns about feasibility, the heterogeneity of cluster characteristics, and the desire for simultaneous clinical evaluation and implementation. In this paper we compare the potential benefits of SW-CRTs against the ethical and epistemic challenges brought forth by the design and suggest that the choice of SW-CRT design must balance epistemic, feasibility and ethical justifications. Moreover, given their complexity, such studies need rigorous and informed ethical oversight.
Collapse
Affiliation(s)
- Carole A Federico
- Stanford Center for Biomedical Ethics, Stanford University, Stanford, CA 94305, USA
| | - Patrick J Heagerty
- Department of Biostatistics, University of Washington, Seattle, WA 98185, USA
| | - John Lantos
- Children's Mercy Hospital Bioethics Center, University of Missouri-Kansas City, Kansas City, MO 64108, USA
| | | | - Vasiliki Rahimzadeh
- Stanford Center for Biomedical Ethics, Stanford University, Stanford, CA 94305, USA
| | - Jeremy Sugarman
- Berman Institute of Bioethics, Johns Hopkins University, Baltimore, MD 21218, USA
| | - Kevin Weinfurt
- Center for Health Measurement, Duke University, Durham, NC 27701, USA
| | - David Wendler
- Department of Bioethics, NIH Clinical Center, Bethesda, MD 20892, USA
| | - Benjamin S Wilfond
- Treuman Katz Center for Pediatric Bioethics, Seattle Children's Research Institute, Seattle, WA 98185, USA
| | - David Magnus
- Stanford Center for Biomedical Ethics, Stanford University, Stanford, CA 94305, USA.
| |
Collapse
|
6
|
Hooper R. Key concepts in clinical epidemiology: Stepped wedge trials. J Clin Epidemiol 2021; 137:159-162. [PMID: 33892089 DOI: 10.1016/j.jclinepi.2021.04.003] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/16/2021] [Revised: 04/10/2021] [Accepted: 04/13/2021] [Indexed: 10/21/2022]
Abstract
A stepped wedge trial evaluates an intervention that is implemented over a number of time periods according to a staggered timetable. Stepped wedge trials are usually cluster randomized, the intervention being delivered at some geographical, service or other cluster level. There is considerable variety in the design and conduct of stepped wedge trials in practice. The analysis of a stepped wedge trial often assumes that the effect of the intervention is maintained at a constant level once it has been implemented. It is important when estimating this effect to adjust for a period effect or underlying secular trend, since time is confounded with intervention, and to account for the clustering of outcomes. The advantage often cited for a stepped wedge design is that every cluster ends up getting the intervention, though in any trial design we can offer the intervention preferentially to control clusters after the trial has finished. The real advantage of a stepped wedge design is likely to be practicality or statistical efficiency.
Collapse
Affiliation(s)
- Richard Hooper
- Institute of Population Health Sciences, Queen Mary University of London, London, UK.
| |
Collapse
|
7
|
Byhoff E, Kangovi S, Berkowitz SA, DeCamp M, Dzeng E, Earnest M, Gonzalez CM, Hartigan S, Karani R, Memari M, Roy B, Schwartz MD, Volerman A, DeSalvo K. A Society of General Internal Medicine Position Statement on the Internists' Role in Social Determinants of Health. J Gen Intern Med 2020; 35:2721-2727. [PMID: 32519320 PMCID: PMC7459005 DOI: 10.1007/s11606-020-05934-8] [Citation(s) in RCA: 39] [Impact Index Per Article: 9.8] [Reference Citation Analysis] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/30/2020] [Accepted: 05/18/2020] [Indexed: 02/06/2023]
Affiliation(s)
- Elena Byhoff
- Department of Medicine, Institute for Clinical Research and Health Policy Studies Tufts Medical Center, Tufts University School of Medicine, Boston, MA, USA.
| | - Shreya Kangovi
- Department of Medicine, University of Pennsylvania, Philadelphia, PA, USA
| | - Seth A Berkowitz
- Department of Medicine, University of North Carolina, Chapel Hill, NC, USA
| | - Matthew DeCamp
- Department of Medicine, University of Colorado, Aurora, CO, USA
| | - Elizabeth Dzeng
- Department of Medicine, University of California, San Francisco, CA, USA
| | - Mark Earnest
- Department of Medicine, University of Colorado, Aurora, CO, USA
| | - Cristina M Gonzalez
- Department of Medicine, Albert Einstein College of Medicine, Montefiore Medical Center, Bronx, NY, USA
| | - Sarah Hartigan
- Department of Medicine, Virginia Commonwealth University, Midlothian, VA, USA
| | - Reena Karani
- Department of Medicine, Medicine and Geriatrics and Palliative Medicine Icahn School of Medicine at Mount Sinai, New York, NY, USA
| | - Milad Memari
- Departments of Medical Education, Johns Hopkins University School of Medicine, Baltimore, MD, USA
| | - Brita Roy
- Department of Medicine, Yale Medicine, New Haven, CT, USA
| | - Mark D Schwartz
- Departments of Population Health and of Medicine, NYU Grossman School of Medicine, New York, NY, USA
| | - Anna Volerman
- Department of Medicine, University of Chicago, Chicago, IL, USA
| | | |
Collapse
|
8
|
Hemming K, Taljaard M. Reflection on modern methods: when is a stepped-wedge cluster randomized trial a good study design choice? Int J Epidemiol 2020; 49:1043-1052. [PMID: 32386407 PMCID: PMC7394949 DOI: 10.1093/ije/dyaa077] [Citation(s) in RCA: 56] [Impact Index Per Article: 14.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/01/2020] [Accepted: 04/08/2020] [Indexed: 12/25/2022] Open
Abstract
The stepped-wedge cluster randomized trial (SW-CRT) involves the sequential transition of clusters (such as hospitals, public health units or communities) from control to intervention conditions in a randomized order. The use of the SW-CRT is growing rapidly. Yet the SW-CRT is at greater risks of bias compared with the conventional parallel cluster randomized trial (parallel-CRT). For this reason, the CONSORT extension for SW-CRTs requires that investigators provide a clear justification for the choice of study design. In this paper, we argue that all other things being equal, the SW-CRT is at greater risk of bias due to misspecification of the secular trends at the analysis stage. This is particularly problematic for studies randomizing a small number of heterogeneous clusters. We outline the potential conditions under which an SW-CRT might be an appropriate choice. Potentially appropriate and often overlapping justifications for conducting an SW-CRT include: (i) the SW-CRT provides a means to conduct a randomized evaluation which otherwise would not be possible; (ii) the SW-CRT facilitates cluster recruitment as it enhances the acceptability of a randomized evaluation either to cluster gatekeepers or other stakeholders; (iii) the SW-CRT is the only feasible design due to pragmatic and logistical constraints (for example the roll-out of a scare resource); and (iv) the SW-CRT has increased statistical power over other study designs (which will include situations with a limited number of clusters). As the number of arguments in favour of an SW-CRT increases, the likelihood that the benefits of using the SW-CRT, as opposed to a parallel-CRT, outweigh its risks also increases. We argue that the mere popularity and novelty of the SW-CRT should not be a factor in its adoption. In situations when a conventional parallel-CRT is feasible, it is likely to be the preferred design.
Collapse
Affiliation(s)
- Karla Hemming
- Institute of Applied Health Research, University of Birmingham, Birmingham, UK
| | - Monica Taljaard
- Clinical Epidemiology Program, Ottawa Hospital Research Institute, Ottawa, ON, Canada
- School of Epidemiology and Public Health, University of Ottawa, Ottawa, ON, Canada
| |
Collapse
|
9
|
Weijer C, Taljaard M. Ottawa Statement does not impede randomised evaluation of government health programmes. JOURNAL OF MEDICAL ETHICS 2020; 46:31-33. [PMID: 31772117 PMCID: PMC6984060 DOI: 10.1136/medethics-2019-105938] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Subscribe] [Scholar Register] [Received: 11/02/2019] [Accepted: 11/13/2019] [Indexed: 06/10/2023]
Abstract
In this issue of JME, Watson et al call for research evaluation of government health programmes and identify ethical guidance, including the Ottawa Statement on the ethical design and conduct of cluster randomised trials, as a hindrance. While cluster randomised trials of health programmes as a whole should be evaluated by research ethics committees (RECs), Watson et al argue that the health programme per se is not within the researcher's control or responsibility and, thus, is out of scope for ethics review. We argue that this view is wrong. The scope of research ethics review is not defined by researcher control or responsibility, but rather by the protection of research participants. And the randomised evaluation of health programmes impacts the liberty and welfare interests of participants insofar as they may be exposed to a harmful programme or denied access to a beneficial one. Further, Watson et al's claim that 'study programmes … would occur whether or not there were any … research activities' is incorrect in the case of cluster randomised designs. In a cluster randomised trial, the government does not implement a programme as usual. Rather, researchers collaborate with the government to randomise clusters to intervention or control conditions in order to rigorously evaluate the programme. As a result, equipoise issues are triggered that must be addressed by the REC.
Collapse
Affiliation(s)
- Charles Weijer
- Rotman Institute of Philosophy, Western University, London, Ontario, Canada
| | - Monica Taljaard
- Clinical Epidemiology Program, Ottawa Hospital Research Institute, Ottawa, Ontario, Canada
| |
Collapse
|