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Sullivan K, Sullivan B. Does nirsevimab prevent lower respiratory infections caused by respiratory syncytial virus? J Perinatol 2024; 44:767-769. [PMID: 38637681 DOI: 10.1038/s41372-024-01970-y] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/25/2024] [Revised: 04/01/2024] [Accepted: 04/11/2024] [Indexed: 04/20/2024]
Affiliation(s)
- Kelsey Sullivan
- Division of Neonatology, Department of Pediatrics, University of Virginia, Charlottesville, VA, USA.
| | - Brynne Sullivan
- Division of Neonatology, Department of Pediatrics, University of Virginia, Charlottesville, VA, USA
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2
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Wang X, Deliu N, Narita Y, Chakraborty B. Incorporating participants' welfare into sequential multiple assignment randomized trials. Biometrics 2024; 80:ujad004. [PMID: 38364800 DOI: 10.1093/biomtc/ujad004] [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: 10/26/2022] [Revised: 07/02/2023] [Accepted: 11/03/2023] [Indexed: 02/18/2024]
Abstract
Dynamic treatment regimes (DTRs) are sequences of decision rules that recommend treatments based on patients' time-varying clinical conditions. The sequential, multiple assignment, randomized trial (SMART) is an experimental design that can provide high-quality evidence for constructing optimal DTRs. In a conventional SMART, participants are randomized to available treatments at multiple stages with balanced randomization probabilities. Despite its relative simplicity of implementation and desirable performance in comparing embedded DTRs, the conventional SMART faces inevitable ethical issues, including assigning many participants to the empirically inferior treatment or the treatment they dislike, which might slow down the recruitment procedure and lead to higher attrition rates, ultimately leading to poor internal and external validities of the trial results. In this context, we propose a SMART under the Experiment-as-Market framework (SMART-EXAM), a novel SMART design that holds the potential to improve participants' welfare by incorporating their preferences and predicted treatment effects into the randomization procedure. We describe the steps of conducting a SMART-EXAM and evaluate its performance compared to the conventional SMART. The results indicate that the SMART-EXAM can improve the welfare of the participants enrolled in the trial, while also achieving a desirable ability to construct an optimal DTR when the experimental parameters are suitably specified. We finally illustrate the practical potential of the SMART-EXAM design using data from a SMART for children with attention-deficit/hyperactivity disorder.
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Affiliation(s)
- Xinru Wang
- Centre for Quantitative Medicine, Duke-NUS Medical School, 169857, Singapore
| | - Nina Deliu
- MEMOTEF Department, Sapienza University of Rome, Rome, 00161, Italy
- MRC-Biostatistics Unit, University of Cambridge, Cambridge, CB2 0SR, United Kingdom
| | - Yusuke Narita
- Department of Economics and Cowles Foundation, Yale University, New Haven, CT, 06520-8281, United States
| | - Bibhas Chakraborty
- Centre for Quantitative Medicine, Duke-NUS Medical School, 169857, Singapore
- Program in Health Services and Systems Research, Duke-NUS Medical School, 169857, Singapore
- Department of Statistics and Data Science, National University of Singapore, 117546, Singapore
- Department of Biostatistics and Bioinformatics, Duke University, Durham, NC, 27710, United States
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3
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Gupta S, Jain S, Yeh J, Guddati AK. Unequal allotment of patients in phase III oncology clinical trials. Am J Cancer Res 2021; 11:3735-3741. [PMID: 34354872 PMCID: PMC8332855] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/09/2021] [Accepted: 05/10/2021] [Indexed: 06/13/2023] Open
Abstract
Patient enrollment in cancer clinical trials has traditionally been limited to an equal distribution between cases and controls, however recently some clinical trials have utilized an unequal distribution between the case and control arms. Trends and proportion of phase 3 cancer clinical trials that have an unequal allocation between the years 2010 and 2019 were studied from data extracted from clinicaltrials.gov. 323 trials with two arms and 35 trials with 3 arms were identified as randomized control trials with the primary purpose of a cancer-related treatment that provided allocation data. Amongst the trials with two arms, 238 trials had equal allocation and 85 trials had unequal allocation. Therefore, cancer clinical trials with unequal allocation represent about one in four 2-arm phase 3 trials. Amongst the eligible trials with three arms, 26 trials had equal allocation and 9 trials had unequal allocation. There was no significant difference in the annual proportion of trials with unequal allocation from 2010 to 2019. The categories of cancer which had the highest number of unequally allotted two-arm clinical trials were: gastrointestinal, breast, and genitourinary malignancies. This shift may represent a new trend in clinical trial design to help enhance closer monitoring of adverse events despite higher costs and lower statistical power attached to this method.
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Affiliation(s)
- Shruti Gupta
- Medical College of Georgia, Augusta UniversityAugusta, GA 30909, USA
| | - Shefali Jain
- Medical College of Georgia, Augusta UniversityAugusta, GA 30909, USA
| | - Justin Yeh
- Medical College of Georgia, Augusta UniversityAugusta, GA 30909, USA
| | - Achuta Kumar Guddati
- Division of Hematology/Oncology, Georgia Cancer Center, Augusta UniversityAugusta, GA 30909, USA
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4
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Walter SD, Bian M. Relative efficiencies of alternative preference-based designs for randomised trials. Stat Methods Med Res 2020; 29:3783-3803. [PMID: 32703124 DOI: 10.1177/0962280220941874] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Recent work has shown that outcomes in clinical trials can be affected by which treatment the trial participants would select if they were allowed to do so, and if they do or do not actually receive that treatment. These influences are known as selection and preference effects, respectively. Unfortunately, they cannot be evaluated in conventional, parallel group trials because patient preferences remain unknown. However, several alternative designs have been proposed, to measure and take account of patient preferences. In this paper, we discuss three preference-based designs (the two-stage, fully randomised, and partially randomised designs). In conventional trials, only the treatment effect is estimable, while the preference-based designs have the potential to estimate some or all of the selection and preference effects. The relative efficiency of these designs is affected by several factors, including the proportion of participants who are undecided about treatments, or who are unable or unwilling to state a preference; the relative preference rate between the treatments being compared, among patients who do have a preference; and the ratio of patients randomised to each treatment. We also discuss the advantages and disadvantages of these designs under different scenarios.
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Affiliation(s)
- S D Walter
- Department of Health Research Methodology, Evidence, and Impact, McMaster University, Hamilton, ON, Canada
| | - M Bian
- Department of Mathematics & Statistics, McMaster University, Hamilton, ON, Canada
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5
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Chandereng T, Wei X, Chappell R. Imbalanced randomization in clinical trials. Stat Med 2020; 39:2185-2196. [PMID: 32246484 DOI: 10.1002/sim.8539] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/15/2019] [Revised: 02/17/2020] [Accepted: 03/07/2020] [Indexed: 11/07/2022]
Abstract
Randomization is a common technique used in clinical trials to eliminate potential bias and confounders in a patient population. Equal allocation to treatment groups is the standard due to its optimal efficiency in many cases. However, in certain scenarios, unequal allocation can improve efficiency. In superiority trials with more than two groups, the optimal randomization is not always a balanced randomization. In noninferiority (NI) trials, additive margin with equal variance is the http://www.statlab.wisc.edu/shiny/SSNI/.
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Affiliation(s)
- Thevaa Chandereng
- Department of Statistics, University of Wisconsin-Madison, Wisconsin, USA.,Department of Biostatistics & Medical Informatics, University of Wisconsin-Madison, Wisconsin, USA.,Morgridge Institute of Research, Wisconsin, USA
| | - Xiaodan Wei
- Biostatistics and Programming, Sanofi Bridgewater, New Jersey, USA
| | - Rick Chappell
- Department of Statistics, University of Wisconsin-Madison, Wisconsin, USA.,Department of Biostatistics & Medical Informatics, University of Wisconsin-Madison, Wisconsin, USA
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6
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Byrne MM, Thompson P. Collective Equipoise, Disappointment, and the Therapeutic Misconception: On the Consequences of Selection for Clinical Research. Med Decis Making 2016; 26:467-79. [PMID: 16997925 DOI: 10.1177/0272989x06290499] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
Abstract
Private information induces individuals to self-select as subjects into clinical research trials, and it induces researchers to select which trials they conduct. The authors show that selection can induce ex ante therapeutic misconception and ex post disappointment among research subjects, and it undermines the rationale of collective equipoise as an ethical basis for clinical trials. Selection provides a reason to make nontrivial payments to subjects, and it implies that researchers should not design experiments to maximize statistical power.
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Affiliation(s)
- Margaret M Byrne
- Department of Epidemiology and Public Health, University of Miami, Florida 33101, USA.
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7
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Amann J, Zanini C, Rubinelli S. What Online User Innovation Communities Can Teach Us about Capturing the Experiences of Patients Living with Chronic Health Conditions. A Scoping Review. PLoS One 2016; 11:e0156175. [PMID: 27272912 PMCID: PMC4896620 DOI: 10.1371/journal.pone.0156175] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/20/2015] [Accepted: 05/10/2016] [Indexed: 11/24/2022] Open
Abstract
BACKGROUND In order to adapt to societal changes, healthcare systems need to switch from a disease orientation to a patient-centered approach. Virtual patient networks are a promising tool to favor this switch and much can be learned from the open and user innovation literature where the involvement of online user communities in the innovation process is well-documented. OBJECTIVES The objectives of this study were 1) to describe the use of online communities as a tool to capture and harness innovative ideas of end users or consumers; and 2) to point to the potential value and challenges of these virtual platforms to function as a tool to inform and promote patient-centered care in the context of chronic health conditions. METHODS A scoping review was conducted. A total of seven databases were searched for scientific articles published in English between 1995 and 2014. The search strategy was refined through an iterative process. RESULTS A total of 144 studies were included in the review. Studies were coded inductively according to their research focus to identify groupings of papers. The first set of studies focused on the interplay of factors related to user roles, motivations, and behaviors that shape the innovation process within online communities. Studies of the second set examined the role of firms in online user innovation initiatives, identifying different organizational strategies and challenges. The third set of studies focused on the idea selection process and measures of success with respect to online user innovation initiatives. Finally, the findings from the review are presented in the light of the particularities and challenges discussed in current healthcare research. CONCLUSION The present paper highlights the potential of virtual patient communities to inform and promote patient-centered care, describes the key challenges involved in this process, and makes recommendations on how to address them.
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Affiliation(s)
- Julia Amann
- Department of Health Sciences and Health Policy, University of Lucerne and Swiss Paraplegic Research, Lucerne/Nottwil, Switzerland
- Swiss Paraplegic Research, Nottwil, Switzerland
| | - Claudia Zanini
- Department of Health Sciences and Health Policy, University of Lucerne and Swiss Paraplegic Research, Lucerne/Nottwil, Switzerland
- Swiss Paraplegic Research, Nottwil, Switzerland
| | - Sara Rubinelli
- Department of Health Sciences and Health Policy, University of Lucerne and Swiss Paraplegic Research, Lucerne/Nottwil, Switzerland
- Swiss Paraplegic Research, Nottwil, Switzerland
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Genovese MC, van Vollenhoven RF, Pacheco-Tena C, Zhang Y, Kinnman N. VX-509 (Decernotinib), an Oral Selective JAK-3 Inhibitor, in Combination With Methotrexate in Patients With Rheumatoid Arthritis. Arthritis Rheumatol 2016; 68:46-55. [PMID: 26473751 DOI: 10.1002/art.39473] [Citation(s) in RCA: 95] [Impact Index Per Article: 11.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/21/2015] [Accepted: 09/15/2015] [Indexed: 12/11/2022]
Abstract
OBJECTIVE To assess the efficacy and safety of decernotinib (VX-509), an oral selective inhibitor of JAK-3, in patients with rheumatoid arthritis (RA) in whom the response to methotrexate treatment was inadequate. METHODS In this 24-week, double-blind, randomized phase IIb study, 358 patients with active RA received either placebo (n = 71) or VX-509 at dosages of 100 mg/day (n = 71), 150 mg/day (n = 72), 200 mg/day (n = 72), or 100 mg twice daily (n = 72). Primary measures of efficacy at week 12 were the response rate according to the American College of Rheumatology 20% improvement criteria (ACR20) and change from baseline in the Disease Activity Score in 28 joints using the C-reactive protein level (DAS28-CRP). RESULTS At week 12, the ACR20 response rates were 46.5%, 66.7%, 56.9%, and 68.1% in the groups receiving VX-509 at dosages of 100 mg/day, 150 mg/day, 200 mg/day, and 100 mg twice daily, respectively, and 18.3% in the placebo group (P < 0.001 for all comparisons). At week 12, the mean change from baseline in the DAS28-CRP was significantly greater in each VX-509 group compared with the placebo group (P < 0.001). Improvements were maintained at week 24, as shown by the ACR20, ACR50, and ACR70 response rates and mean change from baseline in the DAS28-CRP. The most common adverse event in the VX-509 group was headache (8.7%), and elevated levels of transaminases, lipoproteins, and creatinine were observed. CONCLUSION VX-509 significantly improved the signs and symptoms of RA at weeks 12 and 24 compared with the placebo group when it was administered in combination with methotrexate. Safety signals included infection and increases in liver transaminase and lipid levels.
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Affiliation(s)
| | | | | | - Yanqiong Zhang
- Vertex Pharmaceuticals Incorporated, Boston, Massachusetts
| | - Nils Kinnman
- Vertex Pharmaceuticals Incorporated, Boston, Massachusetts
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9
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Dibao-Dina C, Caille A, Giraudeau B. Unbalanced rather than balanced randomized controlled trials are more often positive in favor of the new treatment: an exposed and nonexposed study. J Clin Epidemiol 2015; 68:944-9. [PMID: 25892193 DOI: 10.1016/j.jclinepi.2015.03.007] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/17/2014] [Revised: 02/05/2015] [Accepted: 03/18/2015] [Indexed: 10/23/2022]
Abstract
OBJECTIVES We aimed to assess whether the clinical equipoise principle is satisfied in unbalanced randomized controlled trials (RCTs) (i.e., with an unequal probability of subjects being allocated to one group than another). STUDY DESIGN AND SETTING Observational and comparative study between unbalanced and balanced RCTs. We searched the "core clinical journals" of MEDLINE to identify reports of two-parallel group superiority unbalanced RCTs published between January 2009 and December 2010. For each unbalanced RCT, we identified a maximum of four reports (to maximize power) of matched balanced RCTs dealing with the same population. Our primary outcome was the proportion of positive RCTs [i.e., with statistically significant results for the primary outcome (P < 0.05), showing greater efficacy with the new treatment than the control treatment]. RESULTS We selected 46 reports of unbalanced RCTs and 164 of balanced RCTs; 65.2% unbalanced RCTs and 43.9% of balanced RCTs were positive (odds ratio, 2.38; 95% confidence interval: 1.23, 4.63). As compared with balanced RCTs, unbalanced RCTs were more often industry funded and their control treatments were more often inactive. Adjusting for these latter variables did not modify the results. CONCLUSION This result questions the respect of clinical equipoise in unbalanced RCTs.
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Affiliation(s)
- Clarisse Dibao-Dina
- INSERM U 1153, Hôtel-Dieu, 1 place du parvis Notre-Dame, 75004 Paris, France; INSERM CIC 1415, Hôpital Bretonneau, CHRU de Tours, 2 boulevard Tonnellé, 37044 Tours cedex 9, France; Université François-Rabelais de Tours, PRES Centre-Val de Loire Université, 60 rue du Plat d'Etain, 37020 Tours cedex 1, France; Département Universitaire de Médecine Générale, Université François-Rabelais de Tours, PRES Centre-Val de Loire Université, 10 boulevard Tonnellé, BP 3223, 37044 Tours cedex 1, France.
| | - Agnès Caille
- INSERM U 1153, Hôtel-Dieu, 1 place du parvis Notre-Dame, 75004 Paris, France; INSERM CIC 1415, Hôpital Bretonneau, CHRU de Tours, 2 boulevard Tonnellé, 37044 Tours cedex 9, France; Université François-Rabelais de Tours, PRES Centre-Val de Loire Université, 60 rue du Plat d'Etain, 37020 Tours cedex 1, France; CHRU de Tours, 2 boulevard Tonnellé, 37044 Tours cedex 9, France
| | - Bruno Giraudeau
- INSERM U 1153, Hôtel-Dieu, 1 place du parvis Notre-Dame, 75004 Paris, France; INSERM CIC 1415, Hôpital Bretonneau, CHRU de Tours, 2 boulevard Tonnellé, 37044 Tours cedex 9, France; Université François-Rabelais de Tours, PRES Centre-Val de Loire Université, 60 rue du Plat d'Etain, 37020 Tours cedex 1, France; CHRU de Tours, 2 boulevard Tonnellé, 37044 Tours cedex 9, France
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10
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Dibao-Dina C, Caille A, Sautenet B, Chazelle E, Giraudeau B. Rationale for unequal randomization in clinical trials is rarely reported: a systematic review. J Clin Epidemiol 2014; 67:1070-5. [DOI: 10.1016/j.jclinepi.2014.05.015] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/16/2013] [Revised: 05/20/2014] [Accepted: 05/26/2014] [Indexed: 11/26/2022]
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Ruwaard J, Schrieken B, Schrijver M, Broeksteeg J, Dekker J, Vermeulen H, Lange A. Standardized web-based cognitive behavioural therapy of mild to moderate depression: a randomized controlled trial with a long-term follow-up. Cogn Behav Ther 2010; 38:206-21. [PMID: 19221919 DOI: 10.1080/16506070802408086] [Citation(s) in RCA: 121] [Impact Index Per Article: 8.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/21/2022]
Abstract
Depression is common but undertreated. Web-based self-help provides a widely accessible treatment alternative for mild to moderate depression. However, the lack of therapist guidance may limit its efficacy. The authors assess the efficacy of therapist-guided web-based cognitive behavioural treatment (web-CBT) of mild to moderate depression. Fifty-four individuals with chronic, moderate depression participated in a randomized wait-list controlled trial, with an 18-month follow-up (immediate treatment: n = 36, wait-list control: n = 18). Primary outcome measures were the Beck Depression Inventory (BDI-IA) and the Depression scale of the Symptom Checklist-90-Revised (SCL-90-R. DEP). Secondary outcome measures were the Depression Anxiety Stress Scales and the Well-Being Questionnaire. Five participants (9%) dropped out. Intention-to-treat analyses of covariance revealed that participants in the treatment condition improved significantly more than those in the wait-list control condition (.011 < p < .015). With regard to the primary measures, between-group effects (d) were 0.7 for the BDI-IA and 1.1 for the SCL-90-R DEP. Posttest SCL-90- R DEP scores indicated recovery of 49% of the participants in the treatment group compared with 6% in the control group (odds ratio = 14.5; p < .004). On average, the effects were stable up to 18 months (n = 39), although medication was a strong predictor of relapse. The results demonstrate the efficacy of web-CBT for mild to moderate depression and the importance of therapist guidance in psychological interventions.
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McCann SK, Campbell MK, Entwistle VA. Reasons for participating in randomised controlled trials: conditional altruism and considerations for self. Trials 2010; 11:31. [PMID: 20307273 PMCID: PMC2848220 DOI: 10.1186/1745-6215-11-31] [Citation(s) in RCA: 196] [Impact Index Per Article: 14.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/10/2009] [Accepted: 03/22/2010] [Indexed: 12/04/2022] Open
Abstract
Background Randomised controlled trials of healthcare interventions depend on the participation of volunteers who might not derive any personal health benefit from their participation. The idea that altruistic-type motives are important for trial participation is understandably widespread, but recent studies suggest considerations of personal benefit can influence participation decisions in various ways. Methods Non-participant observation of recruitment consultations (n = 25) and in-depth interviews with people invited to participate in the UK REFLUX trial (n = 13). Results Willingness to help others and to contribute towards furthering medical knowledge featured strongly among the reasons people gave for being interested in participating in the trial. But decisions to attend recruitment appointments and take part were not based solely on consideration of others. Rather, they were presented as conditional on individuals additionally perceiving some benefit (and no significant disadvantage) for themselves. Potential for personal benefit or disadvantage could be seen in both the interventions being evaluated and trial processes. Conclusions The term 'conditional altruism' concisely describes the willingness to help others that may initially incline people to participate in a trial, but that is unlikely to lead to trial participation in practice unless people also recognise that participation will benefit them personally. Recognition of conditional altruism has implications for planning trial recruitment communications to promote informed and voluntary trial participation. Trial registration ISRCTN15517081
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Affiliation(s)
- Sharon K McCann
- Health Services Research Unit, University of Aberdeen, Aberdeen, UK.
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13
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Vail DM. Cancer Clinical Trials: Development and Implementation. Vet Clin North Am Small Anim Pract 2007; 37:1033-57; v. [DOI: 10.1016/j.cvsm.2007.06.007] [Citation(s) in RCA: 33] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
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Canvin K, Jacoby A. Duty, desire or indifference? A qualitative study of patient decisions about recruitment to an epilepsy treatment trial. Trials 2006; 7:32. [PMID: 17163988 PMCID: PMC1770934 DOI: 10.1186/1745-6215-7-32] [Citation(s) in RCA: 73] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/12/2006] [Accepted: 12/12/2006] [Indexed: 11/10/2022] Open
Abstract
BACKGROUND Epilepsy is a common neurological condition, in which drugs are the mainstay of treatment and drugs trials are commonplace. Understanding why patients might or might not opt to participate in epilepsy drug trials is therefore of some importance, particularly at a time of rapid drug development and testing; and the findings may also have wider applicability. This study examined the role of patient perceptions in the decision-making process about recruitment to an RCT (the SANAD Trial) that compared different antiepileptic drug treatments for the management of new-onset seizures and epilepsy. METHODS In-depth interviews with 23 patients recruited from four study centres. All interviews were tape-recorded and transcribed; the transcripts were analysed thematically using a qualitative data analysis package. RESULTS Of the nineteen informants who agreed to participate in SANAD, none agreed for purely altruistic reasons. The four informants who declined all did so for very specific reasons of self-interest. Informants' perceptions of the nature of the trial, of the drugs subject to trial, and of their own involvement were all highly influential in their decision-making. Informants either perceived the trial as potentially beneficial or unlikely to be harmful, and so agreed to participate; or as potentially harmful or unlikely to be beneficial and so declined to participate. CONCLUSION Most patients applied 'weak altruism', while maintaining self-interest. An emphasis on the safety and equivalence of treatments allowed some patients to be indifferent to the question of involvement. There was evidence that some participants were subject to 'therapeutic misconceptions'. The findings highlight the individual nature of trials but nonetheless raise some generic issues in relation to their design and conduct.
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Affiliation(s)
- Krysia Canvin
- Division of Public Health, University of Liverpool, Liverpool, UK
| | - Ann Jacoby
- Division of Public Health, University of Liverpool, Liverpool, UK
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15
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Haris A, Sherrard DJ, Hercz G. Reversal of adynamic bone disease by lowering of dialysate calcium. Kidney Int 2006; 70:931-7. [PMID: 16837920 DOI: 10.1038/sj.ki.5001666] [Citation(s) in RCA: 52] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
Adynamic bone disease (ABD) is increasingly recognized, especially in dialysis patients treated with oral calcium carbonate, vitamin D supplements, or supraphysiological dialysate calcium. We undertook this study to assess the effect of lowering dialysate calcium on episodes of hypercalcemia, serum parathyroid hormone (PTH) levels as well as bone turnover. Fifty-one patients treated with peritoneal dialysis and biopsy-proven ABD were randomized to treatment with control calcium, 1.62 mM, or low calcium, 1.0 mM, dialysate calcium over a 16-month period. In the low dialysate calcium group, 14 patients completed the study. This group experienced a decrease in serum total and ionized calcium levels, and an 89% reduction in episodes of hypercalcemia, resulting in a 300% increase in serum PTH values, from 6.0+/-1.6 to 24.9+/-3.6 pM (P<0.0001). Bone formation rates, all initially suppressed, at 18.1+/-5.6 microm2/mm2/day rose to 159+/-59.4 microm2/mm2/day (P<0.05), into the normal range (>108 microm2/mm2/day). In the control group, nine patients completed the study. Their PTH levels did not increase significantly, from 7.3+/-1.6 to 9.4+/-1.5 pM and bone formation rates did not change significantly either, from 13.3+/-7.1 to 40.9+/-11.9 microm2/mm2/day. Lowering of peritoneal dialysate calcium reduced serum calcium levels and hypercalcemic episodes, which resulted in increased PTH levels and normalization of bone turnover in patients with ABD.
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Affiliation(s)
- A Haris
- Department of Nephrology, St Margit Hospital, Budapest, Hungary, and Department of Medicine, Veterans Administration Hospital and University of Washington, Seattle, USA.
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16
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Spriggs M. Can children be altruistic research subjects? THE AMERICAN JOURNAL OF BIOETHICS : AJOB 2006; 6:49-50. [PMID: 16997827 DOI: 10.1080/15265160600862445] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/11/2023]
Affiliation(s)
- Merle Spriggs
- Murdoch Childrens Research Institute, University of Melbourne, Monash University
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17
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Jafari P, Ayatollahi SMT, Behboodian J. Sequential boundaries approach in clinical trials with unequal allocation ratios. BMC Med Res Methodol 2006; 6:1. [PMID: 16412232 PMCID: PMC1382245 DOI: 10.1186/1471-2288-6-1] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/21/2005] [Accepted: 01/13/2006] [Indexed: 11/30/2022] Open
Abstract
Background In clinical trials, both unequal randomization design and sequential analyses have ethical and economic advantages. In the single-stage-design (SSD), however, if the sample size is not adjusted based on unequal randomization, the power of the trial will decrease, whereas with sequential analysis the power will always remain constant. Our aim was to compare sequential boundaries approach with the SSD when the allocation ratio (R) was not equal. Methods We evaluated the influence of R, the ratio of the patients in experimental group to the standard group, on the statistical properties of two-sided tests, including the two-sided single triangular test (TT), double triangular test (DTT) and SSD by multiple simulations. The average sample size numbers (ASNs) and power (1-β) were evaluated for all tests. Results Our simulation study showed that choosing R = 2 instead of R = 1 increases the sample size of SSD by 12% and the ASN of the TT and DTT by the same proportion. Moreover, when R = 2, compared to the adjusted SSD, using the TT or DTT allows to retrieve the well known reductions of ASN observed when R = 1, compared to SSD. In addition, when R = 2, compared to SSD, using the TT and DTT allows to obtain smaller reductions of ASN than when R = 1, but maintains the power of the test to its planned value. Conclusion This study indicates that when the allocation ratio is not equal among the treatment groups, sequential analysis could indeed serve as a compromise between ethicists, economists and statisticians.
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Affiliation(s)
- Peyman Jafari
- Department of Biostatistics and Epidemiology, Faculty of Health, Shiraz University of Medical Sciences, Shiraz, Iran
| | | | - Javad Behboodian
- Department of Statistics, Faculty of Science, Shiraz University, Shiraz, Iran
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Edwards SJL, Kirchin S. Rationing, randomizing, and researching in health care provision. JOURNAL OF MEDICAL ETHICS 2002; 28:20-23. [PMID: 11834754 PMCID: PMC1733507 DOI: 10.1136/jme.28.1.20] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/23/2023]
Abstract
In this paper the need for valid evidence of the cost-effectiveness of treatments that have not been properly evaluated, yet are already available, albeit in short supply, are examined. Such treatments cannot be withdrawn, pending proper evaluation, nor can they be made more widely available until they have been shown to be cost-effective. As a solution to this impasse the argument put forward recently by Toroyan et al is discussed. They say that randomised controlled trials of such resources could be done but only if resources are randomly allocated independently of a research context. Relevant outcome data could then be collected for research, given this opportunity. (There are already a few investigators who have turned limited resources, mostly health service provision, to their advantage in this way.) We agree. We disagree with Toroyan et al on a number of points. First, they claim that no ethical issue relating to equipoise arises. We disagree and this disagreement depends on our showing that equipoise should be maintained in a relationship that they do not consider. Secondly, they say that consent to data collection is always needed. Again we disagree. Thirdly, they claim that the previous two issues are the only possible ethical issues that could arise. We argue, instead, that there is a further conflict of interests that has ethical import.
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Affiliation(s)
- S J L Edwards
- Centre for Ethics in Medicine, University of Bristol, UK .
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