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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.
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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
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Hoang VT, Nguyen HP, Nguyen VN, Hoang DM, Nguyen TST, Nguyen Thanh L. “Adipose-derived mesenchymal stem cell therapy for the management of female sexual dysfunction: Literature reviews and study design of a clinical trial”. Front Cell Dev Biol 2022; 10:956274. [PMID: 36247008 PMCID: PMC9554747 DOI: 10.3389/fcell.2022.956274] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/30/2022] [Accepted: 07/29/2022] [Indexed: 11/25/2022] Open
Abstract
Hormone imbalance and female sexual dysfunction immensely affect perimenopausal female health and quality of life. Hormone therapy can improve female hormone deficiency, but long-term use increases the risk of cardiovascular diseases and cancer. Therefore, it is necessary to develop a novel effective treatment to achieve long-term improvement in female general and sexual health. This study reviewed factors affecting syndromes of female sexual dysfunction and its current therapy options. Next, the authors introduced research data on mesenchymal stromal cell/mesenchymal stem cell (MSC) therapy to treat female reproductive diseases, including Asherman’s syndrome, premature ovarian failure/primary ovarian insufficiency, and vaginal atrophy. Among adult tissue-derived MSCs, adipose tissue-derived stem cells (ASCs) have emerged as the most potent therapeutic cell therapy due to their abundant presence in the stromal vascular fraction of fat, high proliferation capacity, superior immunomodulation, and strong secretion profile of regenerative factors. Potential mechanisms and side effects of ASCs for the treatment of female sexual dysfunction will be discussed. Our phase I clinical trial has demonstrated the safety of autologous ASC therapy for women and men with sexual hormone deficiency. We designed the first randomized controlled crossover phase II trial to investigate the safety and efficacy of autologous ASCs to treat female sexual dysfunction in perimenopausal women. Here, we introduce the rationale, trial design, and methodology of this clinical study. Because aging and metabolic diseases negatively impact the bioactivity of adult-derived MSCs, this study will use ASCs cultured in physiological oxygen tension (5%) to cope with these challenges. A total of 130 perimenopausal women with sexual dysfunction will receive two intravenous infusions of autologous ASCs in a crossover design. The aims of the proposed study are to evaluate 1) the safety of cell infusion based on the frequency and severity of adverse events/serious adverse events during infusion and follow-up and 2) improvements in female sexual function assessed by the Female Sexual Function Index (FSFI), the Utian Quality of Life Scale (UQOL), and the levels of follicle-stimulating hormone (FSH) and estradiol. In addition, cellular aging biomarkers, including plasminogen activator inhibitor-1 (PAI-1), p16 and p21 expression in T cells and the inflammatory cytokine profile, will also be characterized. Overall, this study will provide essential insights into the effects and potential mechanisms of ASC therapy for perimenopausal women with sexual dysfunction. It also suggests direction and design strategies for future research.
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Affiliation(s)
- Van T. Hoang
- Vinmec Research Institute of Stem Cell and Gene Technology, Vinmec Health Care System, Hanoi, Vietnam
| | - Hoang-Phuong Nguyen
- Vinmec Research Institute of Stem Cell and Gene Technology, Vinmec Health Care System, Hanoi, Vietnam
| | - Viet Nhan Nguyen
- Vinmec International Hospital—Times City, Vinmec Health Care System, Hanoi, Vietnam
- College of Health Science, Vin University, Vinhomes Ocean Park, Hanoi, Vietnam
| | - Duc M. Hoang
- Vinmec Research Institute of Stem Cell and Gene Technology, Vinmec Health Care System, Hanoi, Vietnam
| | - Tan-Sinh Thi Nguyen
- Vinmec International Hospital—Times City, Vinmec Health Care System, Hanoi, Vietnam
| | - Liem Nguyen Thanh
- Vinmec Research Institute of Stem Cell and Gene Technology, Vinmec Health Care System, Hanoi, Vietnam
- Vinmec International Hospital—Times City, Vinmec Health Care System, Hanoi, Vietnam
- College of Health Science, Vin University, Vinhomes Ocean Park, Hanoi, Vietnam
- *Correspondence: Liem Nguyen Thanh,
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Hemming K, Taljaard M, Weijer C, Forbes AB. Use of multiple period, cluster randomised, crossover trial designs for comparative effectiveness research. BMJ 2020; 371:m3800. [PMID: 33148538 DOI: 10.1136/bmj.m3800] [Citation(s) in RCA: 13] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
Affiliation(s)
- Karla Hemming
- Institute of Applied Health Research, University of Birmingham, Birmingham B15 2TT, 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
| | - Charles Weijer
- Departments of Medicine, Epidemiology, and Biostatistics, and Philosophy, Western University, London, ON, Canada
| | - Andrew B Forbes
- School of Public Health and Preventive Medicine, Monash University, Melbourne, VIC, Australia
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Taljaard M, Goldstein CE, Giraudeau B, Nicholls SG, Carroll K, Hey SP, Brehaut JC, Jairath V, London AJ, Eldridge SM, Grimshaw JM, Fergusson DA, Weijer C. Cluster over individual randomization: are study design choices appropriately justified? Review of a random sample of trials. Clin Trials 2020; 17:253-263. [DOI: 10.1177/1740774519896799] [Citation(s) in RCA: 18] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/10/2023]
Abstract
Background: Novel rationales for randomizing clusters rather than individuals appear to be emerging from the push for more pragmatic trials, for example, to facilitate trial recruitment, reduce the costs of research, and improve external validity. Such rationales may be driven by a mistaken perception that choosing cluster randomization lessens the need for informed consent. We reviewed a random sample of published cluster randomized trials involving only individual-level health care interventions to determine (a) the prevalence of reporting a rationale for the choice of cluster randomization; (b) the types of explicit, or if absent, apparent rationales for the use of cluster randomization; (c) the prevalence of reporting patient informed consent for study interventions; and (d) the types of justifications provided for waivers of consent. We considered cluster randomized trials for evaluating exclusively the individual-level health care interventions to focus on clinical trials where individual randomization is only theoretically possible and where there is a general expectation of informed consent. Methods: A random sample of 40 cluster randomized trials were identified by implementing a validated electronic search filter in two electronic databases (Ovid MEDLINE and Embase), with two reviewers independently extracting information from each trial. Inclusion criteria were the following: primary report of a cluster randomized trial, evaluating exclusively an individual-level health care intervention, published between 2007 and 2016, and conducted in Canada, the United States, European Union, Australia, or low- and middle-income country settings. Results: Twenty-five trials (62.5%, 95% confidence interval = 47.5%–77.5%) reported an explicit rationale for the use of cluster randomization. The most commonly reported rationales were those with logistical or administrative convenience (15 trials, 60%) and those that need to avoid contamination (13 trials, 52%); five trials (20%) were cited rationales related to the push for more pragmatic trials. Twenty-one trials (52.5%, 95% confidence interval = 37%–68%) reported written informed consent for the intervention, two (5%) reported verbal consent, and eight (20%) reported waivers of consent, while in nine trials (22.5%) consent was unclear or not mentioned. Reported justifications for waivers of consent included that study interventions were already used in clinical practice, patients were not randomized individually, and the need to facilitate the pragmatic nature of the trial. Only one trial reported an explicit and appropriate justification for waiver of consent based on minimum criteria in international research ethics guidelines, namely, infeasibility and minimal risk. Conclusion: Rationales for adopting cluster over individual randomization and for adopting consent waivers are emerging, related to the need to facilitate pragmatic trials. Greater attention to clear reporting of study design rationales, informed consent procedures, as well as justification for waivers is needed to ensure that such trials meet appropriate ethical standards.
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Affiliation(s)
- Monica Taljaard
- Clinical Epidemiology Program, Ottawa Hospital Research Institute (OHRI), The Ottawa Hospital, Ottawa, ON, Canada
- School of Epidemiology and Public Health, University of Ottawa, Ottawa, ON, Canada
| | - Cory E Goldstein
- Rotman Institute of Philosophy, Western University, London, ON, Canada
| | - Bruno Giraudeau
- Université de Tours, Université de Nantes, INSERM, SPHERE U1246, Tours, France
- INSERM CIC1415, CHRU de Tours, Tours, France
| | - Stuart G Nicholls
- Clinical Epidemiology Program, Ottawa Hospital Research Institute (OHRI), The Ottawa Hospital, Ottawa, ON, Canada
| | - Kelly Carroll
- Clinical Epidemiology Program, Ottawa Hospital Research Institute (OHRI), The Ottawa Hospital, Ottawa, ON, Canada
| | - Spencer Phillips Hey
- Division of Pharmacoepidemiology and Pharmacoeconomics, Department of Medicine, Brigham and Women’s Hospital, Boston, MA, USA
- Center for Bioethics, Harvard Medical School, Boston, MA, USA
| | - Jamie C Brehaut
- Clinical Epidemiology Program, Ottawa Hospital Research Institute (OHRI), The Ottawa Hospital, Ottawa, ON, Canada
- School of Epidemiology and Public Health, University of Ottawa, Ottawa, ON, Canada
| | - Vipul Jairath
- Division of Gastroenterology, Department of Medicine, Western University, London, ON, Canada
- Division of Epidemiology and Biostatistics, University Hospital, Western University, London, ON, Canada
| | - Alex John London
- Department of Philosophy and Center for Ethics and Policy, Carnegie Mellon University, Pittsburgh, PA, USA
| | - Sandra M Eldridge
- Centre for Primary Care and Public Health, Queen Mary University of London, London, UK
| | - Jeremy M Grimshaw
- Clinical Epidemiology Program, Ottawa Hospital Research Institute (OHRI), The Ottawa Hospital, Ottawa, ON, Canada
- School of Epidemiology and Public Health, University of Ottawa, Ottawa, ON, Canada
- Department of Medicine, University of Ottawa, Ottawa, ON, Canada
| | - Dean A Fergusson
- Clinical Epidemiology Program, Ottawa Hospital Research Institute (OHRI), The Ottawa Hospital, Ottawa, ON, Canada
- School of Epidemiology and Public Health, University of Ottawa, Ottawa, ON, Canada
- Department of Medicine, University of Ottawa, Ottawa, ON, Canada
| | - Charles Weijer
- Rotman Institute of Philosophy, Western University, London, ON, Canada
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Goldstein CE, Giraudeau B, Weijer C, Taljaard M. In reply: When and how should we cluster and cross over: methodological and ethical issues (letters 1 and 2). Can J Anaesth 2018; 66:239-240. [PMID: 30341667 DOI: 10.1007/s12630-018-1239-3] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/25/2018] [Accepted: 09/25/2018] [Indexed: 11/28/2022] Open
Affiliation(s)
- Cory E Goldstein
- Rotman Institute of Philosophy, Western University, London, ON, Canada.
| | - Bruno Giraudeau
- Université de Tours, Université de Nantes, INSERM SPHERE, Tours, France.,INSERM CIC, CHRU de Tours, Tours, France
| | - Charles Weijer
- Rotman Institute of Philosophy, Western University, London, ON, Canada
| | - Monica Taljaard
- Rotman Institute of Philosophy, Western University, London, ON, Canada.,Ottawa Hospital Research Institute, Ottawa, ON, Canada.,School of Epidemiology and Public Health, University of Ottawa, Ottawa, ON, Canada
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Lee SF, Bangdiwala SI, Spence J, Connolly S. When and how should we cluster and cross over: methodological and ethical issues (letter 2). Can J Anaesth 2018; 66:237-238. [PMID: 30341666 DOI: 10.1007/s12630-018-1238-4] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/26/2018] [Revised: 08/02/2018] [Accepted: 08/13/2018] [Indexed: 11/24/2022] Open
Affiliation(s)
- Shun Fu Lee
- McMaster University, Population Health Research Institute (PHRI), Hamilton, ON, Canada.
| | - Shrikant I Bangdiwala
- McMaster University, Population Health Research Institute (PHRI), Hamilton, ON, Canada
| | - Jessica Spence
- McMaster University, Population Health Research Institute (PHRI), Hamilton, ON, Canada
| | - Stuart Connolly
- McMaster University, Population Health Research Institute (PHRI), Hamilton, ON, Canada
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