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1.
Pharm Stat ; 19(5): 692-709, 2020 09.
Artigo em Inglês | MEDLINE | ID: mdl-32319194

RESUMO

Investigators who manage multicenter clinical trials need to pay careful attention to patterns of subject accrual, and the prediction of activation time for pending centers is potentially crucial for subject accrual prediction. We propose a Bayesian hierarchical model to predict subject accrual for multicenter clinical trials in which center activation times vary. We define center activation time as the time at which a center can begin enrolling patients in the trial. The difference in activation times between centers is assumed to follow an exponential distribution, and the model of subject accrual integrates prior information for the study with actual enrollment progress. We apply our proposed Bayesian multicenter accrual model to two multicenter clinical studies. The first is the PAIN-CONTRoLS study, a multicenter clinical trial with a goal of activating 40 centers and enrolling 400 patients within 104 weeks. The second is the HOBIT trial, a multicenter clinical trial with a goal of activating 14 centers and enrolling 200 subjects within 36 months. In summary, the Bayesian multicenter accrual model provides a prediction of subject accrual while accounting for both center- and individual patient-level variation.


Assuntos
Ensaios Clínicos como Assunto/métodos , Modelos Estatísticos , Estudos Multicêntricos como Assunto/métodos , Teorema de Bayes , Humanos , Seleção de Pacientes , Fatores de Tempo
2.
Int J Clin Oncol ; 21(1): 28-37, 2016 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-26499195

RESUMO

Recently, the complexity and costs of clinical trials have increased dramatically, especially in the area of new drug development. Risk-based monitoring (RBM) has been attracting attention as an efficient and effective trial monitoring approach, which can be applied irrespectively of the trial sponsor, i.e., academic institution or pharmaceutical company. In the RBM paradigm, it is expected that a statistical approach to central monitoring can help improve the effectiveness of on-site monitoring by prioritizing and guiding site visits according to central statistical data checks, as evidenced by examples of actual trial datasets. In this review, several statistical methods for central monitoring are presented. It is important to share knowledge about the role and performance capabilities of statistical methodology among clinical trial team members (i.e., sponsors, investigators, data managers, monitors, and biostatisticians) in order to adopt central statistical monitoring for assessing data quality in the actual clinical trial.


Assuntos
Ensaios Clínicos como Assunto , Interpretação Estatística de Dados , Humanos
3.
Ther Innov Regul Sci ; 57(6): 1217-1228, 2023 11.
Artigo em Inglês | MEDLINE | ID: mdl-37450198

RESUMO

Monitoring of clinical trials is a fundamental process required by regulatory agencies. It assures the compliance of a center to the required regulations and the trial protocol. Traditionally, monitoring teams relied on extensive on-site visits and source data verification. However, this is costly, and the outcome is limited. Thus, central statistical monitoring (CSM) is an additional approach recently embraced by the International Council for Harmonisation (ICH) to detect problematic or erroneous data by using visualizations and statistical control measures. Existing implementations have been primarily focused on detecting inlier and outlier data. Other approaches include principal component analysis and distribution of the data. Here we focus on the utilization of comparisons of centers to the Grand mean for different model types and assumptions for common data types, such as binomial, ordinal, and continuous response variables. We implement the usage of multiple comparisons of single centers to the Grand mean of all centers. This approach is also available for various non-normal data types that are abundant in clinical trials. Further, using confidence intervals, an assessment of equivalence to the Grand mean can be applied. In a Monte Carlo simulation study, the applied statistical approaches have been investigated for their ability to control type I error and the assessment of their respective power for balanced and unbalanced designs which are common in registry data and clinical trials. Data from the German Multiple Sclerosis Registry (GMSR) including proportions of missing data, adverse events and disease severity scores were used to verify the results on Real-World-Data (RWD).


Assuntos
Esclerose Múltipla , Humanos , Esclerose Múltipla/tratamento farmacológico , Simulação por Computador
4.
Neurorehabil Neural Repair ; 36(10-11): 659-665, 2022 11.
Artigo em Inglês | MEDLINE | ID: mdl-36113101

RESUMO

The record-breaking pace of COVID-19 vaccine development and implementation depended heavily on collaboration among academic, government, and commercial stakeholders, especially through data-sharing and robust multicenter trials. Collaborative efforts have not been as fruitful in fields such as neurorehabilitation, where non-pharmacological interventions play a much larger role. Barriers to translating scientific advancements into clinical practice in neurorehabilitation include pervasively small study sizes, exacerbated by limited funding for non-pharmacological multicenter clinical trials; difficulty standardizing-and adequately describing-non-pharmacological interventions; and a lack of incentives for individual patient-level data-sharing. These barriers prevent reliable meta-analysis of non-pharmacological clinical studies in neurorehabilitation. This point-of-view will highlight these challenges as well as suggest practical steps that may be taken to improve the neurorehabilitation pipeline between evidence and implementation.


Assuntos
COVID-19 , Reabilitação Neurológica , Humanos , Vacinas contra COVID-19 , Motivação , Estudos Multicêntricos como Assunto
5.
Ann Transl Med ; 10(22): 1251, 2022 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-36544630

RESUMO

Background and Objective: The number of new drug clinical trials in China is surging, and ethics review played an important part in clinical trials. However, there are certain problems of ethical review in China. This review aims to conduct a review to propose recommendations of an ethical review mode for multicenter clinical trials and ultimately contribute to improving the ethics review mechanism and the efficiency. Methods: A literature review, publication research and interpretation of the related governmental policies and requirements in China were conducted to collect available information for analysis of the current situation in terms of the various ethical review modes for multicenter clinical research. The literatures and information were searched and selected from national and international database and related governance website by following some inclusion and exclusion criteria. And a comparation with the relevant practical experience in the USA was conducted to support the proposing of recommendations to China by referring to some successful practice in the USA. Key Content and Findings: China has undergone several stages of development. The most traditional and least efficient model is institutional review boards (IRBs) review, which is most commonly used. After IRB review mode, other modes such as central IRB and single IRB review have emerged, which have improved the efficiency of ethical review. However, multiple challenges exist like, no clear definition of regulatory responsibilities and the consensus is not easy to be made due to the gap of interpretation and the unbalanced development on ethic review system from Chinese hospitals. Conclusions: The multicenter ethical review should adopt the conditional 'approval' mode of the leading site's ethical review decisions, gradually establish a single IRB review and select the best ethics committee. Regional ethics committees can gradually take responsibility for the primary review in the multicenter ethics review model and ultimately contribute to improving the mechanism and efficiency of the ethics review.

6.
J Clin Transl Sci ; 5(1): e194, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34888064

RESUMO

Clinical trials continue to face significant challenges in participant recruitment and retention. The Recruitment Innovation Center (RIC), part of the Trial Innovation Network (TIN), has been funded by the National Center for Advancing Translational Sciences of the National Institutes of Health to develop innovative strategies and technologies to enhance participant engagement in all stages of multicenter clinical trials. In collaboration with investigator teams and liaisons at Clinical and Translational Science Award institutions, the RIC is charged with the mission to design, field-test, and refine novel resources in the context of individual clinical trials. These innovations are disseminated via newsletters, publications, a virtual toolbox on the TIN website, and RIC-hosted collaboration webinars. The RIC has designed, implemented, and promised customized recruitment support for 173 studies across many diverse disease areas. This support has incorporated site feasibility assessments, community input sessions, recruitment materials recommendations, social media campaigns, and an array of study-specific suggestions. The RIC's goal is to evaluate the efficacy of these resources and provide access to all investigating teams, so that more trials can be completed on time, within budget, with diverse participation, and with enough accrual to power statistical analyses and make substantive contributions to the advancement of healthcare.

7.
J Clin Epidemiol ; 137: 250-261, 2021 09.
Artigo em Inglês | MEDLINE | ID: mdl-34023433

RESUMO

OBJECTIVE: To assess the reporting quality of randomized controlled trials (RCTs) with multicenter design, particularly whether necessary information related to multicenter characteristics was adequately reported. STUDY DESIGN AND SETTING: Through a search of 4 international electronic databases, we identified multicenter RCTs published in English from 1975 to 2019. Reporting quality was assessed by the CONSORT (Consolidated Standards of Reporting Trials) checklist (37 items) and by a self-designed multicenter-specific checklist (27 items covering multicenter design, implement and analysis). The scores of trials published in three time periods (1975-1995; 1996-2009; and 2010-2019) were also compared. RESULTS: A total of 2,844 multicenter RCTs were included. For the CONSORT checklist, the mean (standard deviation) reporting score was 24.1 (5.5), 12 items were assessed as excellent (>90%), 12 items as good (50%-90%), and 13 items as poor (<50%). For the multicenter checklist, the reporting score was 3.9 (2.2), only 3 items were excellent or good, and the remaining 24 items were poor. Time period comparison showed that reporting quality improved over time, especially after the CONSORT 2010 issued. CONCLUSION: Although CONSORT appears to have enhanced the reporting quality of multicenter RCTs, further improvement is needed. A "CONSORT extension for multicenter trials" should be developed.


Assuntos
Confiabilidade dos Dados , Estudos Multicêntricos como Assunto , Ensaios Clínicos Controlados Aleatórios como Assunto , Projetos de Pesquisa/normas
8.
J Nucl Med ; 56(1): 145-52, 2015 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-25525180

RESUMO

UNLABELLED: The Clinical Trials Network (CTN) of the Society of Nuclear Medicine and Molecular Imaging (SNMMI) operates a PET/CT phantom imaging program using the CTN's oncology clinical simulator phantom, designed to validate scanners at sites that wish to participate in oncology clinical trials. Since its inception in 2008, the CTN has collected 406 well-characterized phantom datasets from 237 scanners at 170 imaging sites covering the spectrum of commercially available PET/CT systems. The combined and collated phantom data describe a global profile of quantitative performance and variability of PET/CT data used in both clinical practice and clinical trials. METHODS: Individual sites filled and imaged the CTN oncology PET phantom according to detailed instructions. Standard clinical reconstructions were requested and submitted. The phantom itself contains uniform regions suitable for scanner calibration assessment, lung fields, and 6 hot spheric lesions with diameters ranging from 7 to 20 mm at a 4:1 contrast ratio with primary background. The CTN Phantom Imaging Core evaluated the quality of the phantom fill and imaging and measured background standardized uptake values to assess scanner calibration and maximum standardized uptake values of all 6 lesions to review quantitative performance. Scanner make-and-model-specific measurements were pooled and then subdivided by reconstruction to create scanner-specific quantitative profiles. RESULTS: Different makes and models of scanners predictably demonstrated different quantitative performance profiles including, in some cases, small calibration bias. Differences in site-specific reconstruction parameters increased the quantitative variability among similar scanners, with postreconstruction smoothing filters being the most influential parameter. Quantitative assessment of this intrascanner variability over this large collection of phantom data gives, for the first time, estimates of reconstruction variance introduced into trials from allowing trial sites to use their preferred reconstruction methodologies. Predictably, time-of-flight-enabled scanners exhibited less size-based partial-volume bias than non-time-of-flight scanners. CONCLUSION: The CTN scanner validation experience over the past 5 y has generated a rich, well-curated phantom dataset from which PET/CT make-and-model and reconstruction-dependent quantitative behaviors were characterized for the purposes of understanding and estimating scanner-based variances in clinical trials. These results should make it possible to identify and recommend make-and-model-specific reconstruction strategies to minimize measurement variability in cancer clinical trials.


Assuntos
Ensaios Clínicos como Assunto , Neoplasias/diagnóstico por imagem , Imagens de Fantasmas , Tomografia por Emissão de Pósitrons/instrumentação , Sociedades Científicas , Tomografia Computadorizada por Raios X/instrumentação , Calibragem , Humanos , Imagem Molecular , Medicina Nuclear
9.
Spine J ; 15(5): 1133-40, 2015 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-25637470

RESUMO

BACKGROUND CONTEXT: Multicenter prospective randomized clinical trials represent the best evidence to support the safety and effectiveness of medical devices. Industry sponsorship of multicenter clinical trials is purported to lead to bias. PURPOSE: To determine what proportion of spine device-related trials are industry-sponsored and the effect of industry sponsorship on trial design. STUDY DESIGN: Analysis of data from a publicly available clinical trials database. METHODS: Clinical trials of spine devices registered on ClinicalTrials.gov, a publicly accessible trial database, were evaluated in terms of design, number and location of study centers, and sample size. The relationship between trial design characteristics and study sponsorship was evaluated using logistic regression and general linear models. RESULTS: One thousand six hundred thrity-eight studies were retrieved from ClinicalTrials.gov using the search term "spine." Of the 367 trials that focused on spine surgery, 200 (54.5%) specifically studied devices for spine surgery and 167 (45.5%) focused on other issues related to spine surgery. Compared with nondevice trials, device trials were far more likely to be sponsored by the industry (74% vs. 22.2%, odds ratio (OR) 9.9 [95% confidence interval 6.1-16.3]). Industry-sponsored device trials were more likely multicenter (80% vs. 29%, OR 9.8 [4.8-21.1]) and had approximately four times as many participating study centers (p<.0001) and larger sample sizes. There were very few US-based multicenter randomized trials of spine devices not sponsored by the industry. CONCLUSIONS: Most device-related spine research is industry-sponsored. Multicenter trials are more likely to be industry-sponsored. These findings suggest that previously published studies showing larger effect sizes in industry-sponsored vs. nonindustry-sponsored studies may be biased as a result of failure to take into account the marked differences in design and purpose.


Assuntos
Equipamentos e Provisões/efeitos adversos , Procedimentos Neurocirúrgicos/instrumentação , Ensaios Clínicos Controlados Aleatórios como Assunto/economia , Coluna Vertebral/cirurgia , Equipamentos e Provisões/economia , Humanos , Indústrias/economia , Estudos Multicêntricos como Assunto/economia , Estudos Multicêntricos como Assunto/métodos , Ensaios Clínicos Controlados Aleatórios como Assunto/métodos
10.
Clin Transl Sci ; 8(1): 57-66, 2015 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-25196592

RESUMO

Reduction of duplicative Institutional Review Board (IRB) review for multiinstitutional studies is a desirable goal to improve IRB efficiency while enhancing human subject protections. Here we describe the Harvard Catalyst Master Reciprocal Common IRB Reliance Agreement (MRA), a system that provides a legal framework for IRB reliance, with the potential to streamline IRB review processes and reduce administrative burden and barriers to collaborative, multiinstitutional research. The MRA respects the legal autonomy of the signatory institutions while offering a pathway to eliminate duplicative IRB review when appropriate. The Harvard Catalyst MRA provides a robust and flexible model for reciprocal reliance that is both adaptable and scalable.


Assuntos
Comitês de Ética em Pesquisa , Estudos Multicêntricos como Assunto , Inovação Organizacional , Comportamento Cooperativo , Humanos , Modelos Teóricos , Faculdades de Medicina , Controle Social Formal
11.
Med 2 0 ; 2(2): e5, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-25075240

RESUMO

BACKGROUND: In recent years, Highly-Active Anti-Retroviral Therapies (HAARTs) have modified the Human Immunodeficiency Virus (HIV) life-cycle and the disease is now considered chronic. Consequently, a longitudinal and complex follow-up is now required for HIV positive patients during their lifetime. Moreover, patients often encounter various complications due to comorbidities, related to the immunodeficiency state and HAARTs' side effects. Thus, HIV positive patients are involved in multicenter clinical trials (MCTs) to improve treatments and discover a preventive vaccine. Therefore, physicians require proper instruments to access comprehensive patient data for managing patients during follow-ups, and tools for data collection and analysis in MCTs. OBJECTIVE: The Ligurian HIV Clinical Network aims to provide physicians with a Web-tool to administrate HIV positive patients' data within primary-care and to reuse the collected clinical information to perform MCTs in Northern Italy. METHODS: The key aspect of the system is a relational database which allows the storage of various types of clinical information (eg, related to HIV, cardiovascular, or hepatic diseases) in multiple formats. The modular design of the database permits a rapid insertion of new parameters without requiring any changes in the database structure. Furthermore, codes from biomedical ontologies controlled vocabularies ("Logical Observation Identifier Names and Codes", and "International Classification of Diseases 9") and ontologies ("Systematized Nomenclature of Medicine Clinical Terms"), units and normality ranges used by all partners participating in the project were collected to achieve a complete semantic interoperability. Accordingly, data can be automatically normalized through the z score formula and physicians can extract and correctly compare information with external statistical tools. Moreover, to respect patients' privacy and legal issues, a local identifier, determined through an HASH cryptography algorithm, is assigned to each patient during the registration process. The database is managed by a user-friendly Web-platform which allows quick access to information during medical examinations and the reusing of the collected data for present and future MCTs. Furthermore, a bidirectional middleware was created in order to import/export information through HL7 messaging. Hence, data can be manually entered by physicians or automatically collected within HL7-compliant Hospital Information systems. RESULTS: Presently, the direct storage of patients' information from the San Paolo Hospital (Savona, Italy), and San Martino and Galliera hospitals in Genoa is in a test phase. Currently, 8 centers of Infectious Diseases (located in Liguria and Piedmont) are participating in the project and almost 400 HIV positive patients have been recorded in the system. Patient data has been used for primary care and research purposes. Currently, there are 4 on-going MCTs and preliminary results have already been presented at International HIV congresses. CONCLUSIONS: The Web-platform allows effective management, sharing and reuse of information within primary care and clinical research. In the future it is planned to share the clinical information from this network with other HL7-compliant workgroups and to extend the platform to other infective diseases (eg, hepatitis).

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