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1.
Regen Med ; 15(1): 1215-1227, 2020 01.
Artigo em Inglês | MEDLINE | ID: mdl-32103712

RESUMO

Aim: We investigated publication rates and reported results for gene- and cell-based therapy trials. Materials & methods: In a cohort of Institutional Review Board (IRB)-authorized trials during 2007-2017 in the Netherlands (n = 105), we examine publication rates and reported results in scientific papers and conference abstracts as well as associations with the occurrence of trial characteristics. Results: The publication rate for scientific papers was 27% and 17% for conference abstracts (median survival time: 1050 days). Academic hospitals published more in scientific papers whereas private sponsors published more in conference abstracts. Manufacturing protocols were underreported compared with clinical outcomes. Most publications reported positive results (78%). Conclusion: Publication rates are currently suboptimal indicating a need for enhanced knowledge sharing to stimulate gene- and cell-based therapy development.


Assuntos
Terapia Baseada em Transplante de Células e Tecidos/estatística & dados numéricos , Ensaios Clínicos como Assunto/estatística & dados numéricos , Terapia Genética/estatística & dados numéricos , Editoração/estatística & dados numéricos , Editoração/tendências , Estudos de Coortes , Humanos , Metanálise como Assunto
2.
F1000Res ; 8: 280, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31497290

RESUMO

Reporting of research findings is often selective. This threatens the validity of the published body of knowledge if the decision to report depends on the nature of the results. Studies on causes and mechanisms underlying selective reporting may help to avoid or reduce reporting bias. Such research should be guided by a theoretical framework of possible causal pathways that lead to reporting bias. We build upon a classification of determinants of selective reporting that we recently developed in a systematic review of the topic. The resulting theoretical framework features four clusters of causes. There are two clusters of necessary causes: (A) motivations (e.g. a preference for positive findings) and (B) means (e.g. a flexible study design). These two combined represent a sufficient cause for reporting bias to occur. The framework also features two clusters of component causes: (C) conflicts and balancing of interests referring to the individual or the team, and (D) pressures from science and society. The component causes may modify the effect of the necessary causes or may lead to reporting bias mediated through the necessary causes. Our theoretical framework is meant to inspire further research and to create awareness among researchers and end-users of research about reporting bias and its causes.


Assuntos
Viés , Projetos de Pesquisa , Revelação
3.
PLoS One ; 13(2): e0188247, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29401492

RESUMO

BACKGROUND: Selective reporting is wasteful, leads to bias in the published record and harms the credibility of science. Studies on potential determinants of selective reporting currently lack a shared taxonomy and a causal framework. OBJECTIVE: To develop a taxonomy of determinants of selective reporting in science. DESIGN: Inductive qualitative content analysis of a random selection of the pertinent literature including empirical research and theoretical reflections. METHODS: Using search terms for bias and selection combined with terms for reporting and publication, we systematically searched the PubMed, Embase, PsycINFO and Web of Science databases up to January 8, 2015. Of the 918 articles identified, we screened a 25 percent random selection. From eligible articles, we extracted phrases that mentioned putative or possible determinants of selective reporting, which we used to create meaningful categories. We stopped when no new categories emerged in the most recently analyzed articles (saturation). RESULTS: Saturation was reached after analyzing 64 articles. We identified 497 putative determinants, of which 145 (29%) were supported by empirical findings. The determinants represented 12 categories (leaving 3% unspecified): focus on preferred findings (36%), poor or overly flexible research design (22%), high-risk area and its development (8%), dependence upon sponsors (8%), prejudice (7%), lack of resources including time (3%), doubts about reporting being worth the effort (3%), limitations in reporting and editorial practices (3%), academic publication system hurdles (3%), unfavorable geographical and regulatory environment (2%), relationship and collaboration issues (2%), and potential harm (0.4%). CONCLUSIONS: We designed a taxonomy of putative determinants of selective reporting consisting of 12 categories. The taxonomy may help develop theory about causes of selection bias and guide policies to prevent selective reporting.


Assuntos
Viés de Publicação , Viés de Seleção
4.
Br J Clin Pharmacol ; 83(12): 2807-2812, 2017 12.
Artigo em Inglês | MEDLINE | ID: mdl-28975652

RESUMO

AIMS: The aims of the present study were to investigate the role of pharmacology in the design of first-in-man (FIM) trials in the Netherlands, and to evaluate the change in design approaches between 2007 and 2015. METHODS: All FIM drug trials approved by all Dutch Institutional Review Boards (IRBs) in 2007 and in 2015 were selected. The original trial protocols, investigator's brochures and investigational medicinal product dossiers were the data sources. The following four design elements were assessed on the justification of the chosen approaches: preclinical information, dose calculation, endpoints, and dose escalation. RESULTS: In 2007, the Dutch IRBs approved 21 FIM trials, and in 2015 they approved 34 FIM trials (55 in total). Seven out of 21 (33%) of the FIM trials from 2007, and 14 out of the 34 (41%) FIM trials from 2015 discussed only the no-observed-adverse-effect level or no-observed-effect level as preclinical information. Furthermore, five of the 21 (24%) 2007 FIM trials and 12 of the 34 (35%) 2015 FIM trials used unexplained allometric scaling. Pharmacodynamic (PD) parameters were measured in 15 of the 21 (71%) 2007 FIM trials and in 31 of the 34 (91%) of the 2015 FIM trials, and allometric scaling was only guided by safety/tolerability in 11 of the 20 (55%) dose escalation trials in 2007 and in nine of the 33 (27%) dose escalation trials in 2015. CONCLUSIONS: Trial protocols and investigator's brochures commonly lack pharmacokinetic/PD approaches. Investigators, sponsors and IRBs should require an upfront consideration of pharmacology in these aspects for all FIM trials.


Assuntos
Ensaios Clínicos como Assunto/métodos , Preparações Farmacêuticas/administração & dosagem , Projetos de Pesquisa/tendências , Bases de Dados Factuais , Relação Dose-Resposta a Droga , Cálculos da Dosagem de Medicamento , Avaliação Pré-Clínica de Medicamentos/tendências , Determinação de Ponto Final/tendências , Humanos , Países Baixos , Nível de Efeito Adverso não Observado , Farmacocinética , Fatores de Tempo
5.
J Clin Epidemiol ; 89: 199-208, 2017 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-28535887

RESUMO

OBJECTIVE: To identify the occurrence and determinants of protocol-publication discrepancies in clinical drug trials. STUDY DESIGN AND SETTING: All published clinical drug trials reviewed by the Dutch institutional review boards in 2007 were analyzed. Discrepancies between trial protocols and publications were measured among key reporting aspects. We evaluated the association of trial characteristics with discrepancies in primary endpoints by calculating the risk ratio (RR) and 95% confidence interval (CI). RESULTS: Of the 334 published trials, 32 (9.6%) had a protocol/publication discrepancy in the primary endpoints. Among the subgroup of randomized controlled trials (RCTs; N = 204), 12 (5.9%) had a discrepancy in the primary endpoint. Investigator-initiated trials with and without industry (co-) funding were associated with having discrepancies in the primary endpoints compared with industry-sponsored trials (RR 3.7; 95% CI 1.4-9.9 and RR 4.4; 95% CI 2.0-9.5, respectively). Furthermore, other than phase 1-4 trials (vs. phase 1; RR 4.6; 95% CI 1.1-19.3), multicenter trials were also conducted outside the European Union (vs. single center; RR 0.2; 95% CI 0.1-0.6), not prospectively registered trials (RR 3.3; 95% CI 1.5-7.5), non-RCTs (vs. superiority RCT; RR 2.4; 95% CI 1.2-4.8) and, among the RCTs, crossover compared with a parallel group design (RR 3.7; 95% CI 1.1-12.3) were significantly associated with having discrepancies in the primary endpoints. CONCLUSIONS: Improvement in completeness of reporting is still needed, especially among investigator-initiated trials and non-RCTs. To eliminate undisclosed discrepancies, trial protocols should be available in the public domain at the same time when the trial is published.


Assuntos
Ensaios Clínicos como Assunto/estatística & dados numéricos , Ensaios Clínicos como Assunto/normas , Avaliação de Medicamentos/normas , Determinação de Ponto Final/estatística & dados numéricos , Estudos de Coortes , Humanos , Viés de Publicação , Editoração
6.
J Clin Epidemiol ; 88: 140-147, 2017 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-28487159

RESUMO

OBJECTIVES: The objective of the study was to identify the reasons for discontinuation of clinical drug trials and to evaluate whether efficacy-related discontinuations were adequately planned in the trial protocol. STUDY DESIGN AND SETTING: All clinical drug trials in the Netherlands, reviewed by institutional review boards in 2007, were followed until December 2015. Data were obtained through the database of the Dutch competent authority (Central Committee on Research Involving Human Subjects [CCMO]) and a questionnaire to the principal investigators. Reasons for trial discontinuation were the primary outcome of the study. Three reasons for discontinuation were analyzed separately: all cause, recruitment failure, and efficacy related (when an interim analysis had demonstrated futility or superiority). Among the efficacy-related discontinuations, we examined whether the data monitoring committee, the stopping rule, and the moment of the interim analysis in the trial progress were specified in the trial protocol. RESULTS: Of the 574 trials, 102 (17.8%) were discontinued. The most common reasons were recruitment failure (33 of 574; 5.7%) and solely efficacy related (30 of 574; 5.2%). Of the efficacy-related discontinuations, 10 of 30 (33.3%) of the trial protocols reported all three aspects in the trial protocol, and 20 of 30 (66.7%) reported at least one aspect in the trial protocol. CONCLUSION: One out of five clinical drug trials is discontinued before the planned trial end, with recruitment failure and futility as the most common reasons. The target sample size of trials should be feasible, and interim analyses should be adequately described in trial protocols.


Assuntos
Ensaios Clínicos como Assunto/estatística & dados numéricos , Término Precoce de Ensaios Clínicos/estatística & dados numéricos , Seleção de Pacientes , Preparações Farmacêuticas , Comitês de Monitoramento de Dados de Ensaios Clínicos , Estudos de Coortes , Humanos , Países Baixos , Tamanho da Amostra
7.
BMJ ; 356: j1526, 2017 03 27.
Artigo em Inglês | MEDLINE | ID: mdl-28347996
8.
J Patient Saf ; 13(4): 217-222, 2017 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-25275383

RESUMO

OBJECTIVE: The aim of this study was to evaluate screening questions for estimating nonsteroidal anti-inflammatory drug (NSAID) risk knowledge. METHODS: Cross-sectional data from a telephone interview of NSAID users 50 years or older from 39 physician practices in Alabama were used. Patient-reported awareness of prescription NSAID risk and health literacy were the independent variables, and a cumulative index score of objectively tested knowledge of 4 prominent NSAID risks was the dependent variable. General linearized latent and mixed model ordered logistic regression was used to estimate associations among the independent variables, covariates, and objectively tested NSAID risk knowledge. Population-averaged probabilities for levels of objectively tested NSAID risk knowledge were subsequently estimated. RESULTS: Subjective awareness of any prescription NSAID risk (adjusted odds ratio [AOR], 2.40; 95% confidence interval [CI], 1.55-3.74), adequate health literacy (AOR, 1.71; 95% CI, 1.04-2.83), and physician counseling about 1 or more NSAID risks (AOR, 1.69; 95% CI, 1.09-2.61) were significantly and positively associated with NSAID risk knowledge. The probability of correctly answering at least 1 of the 4 NSAID risk knowledge questions was 70% in the absence of any subjective risk awareness and in less than adequate health literacy. Whereas the probability of correctly answering at least 1 of the 4 NSAID risk knowledge questions increased to 86% in the presence of subjective awareness of any prescription NSAID risk and adequate health literacy. CONCLUSIONS: Screening questions for subjective NSAID risk awareness and health literacy are predictive of objectively tested NSAID knowledge and can be used to triage patients as well as subsequently initiate and direct a conversation about NSAID risk.


Assuntos
Anti-Inflamatórios não Esteroides/efeitos adversos , Avaliação Pré-Clínica de Medicamentos/métodos , Idoso , Anti-Inflamatórios não Esteroides/farmacologia , Comunicação , Estudos Transversais , Feminino , Conhecimentos, Atitudes e Prática em Saúde , Humanos , Masculino
9.
PLoS One ; 11(12): e0167709, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27973571

RESUMO

The objective of this study was to investigate the occurrence and determinants of non-publication of clinical drug trials in the Netherlands.All clinical drug trials reviewed by the 28 Institutional Review Boards (IRBs) in the Netherlands in 2007 were followed-up from approval to publication. Candidate determinants were the sponsor, phase, applicant, centers, therapeutic effect expected, type of trial, approval status of the drug(s), drug type, participant category, oncology or other disease area, prospective registration, and early termination. The main outcome was publication as peer reviewed article. The percentage of trials that were published, crude and adjusted odds ratio (OR), and 95% confidence interval (CI) were used to quantify the associations between determinants and publication. In 2007, 622 clinical drug trials were reviewed by IRBs in the Netherlands. By the end of follow-up, 19 of these were rejected by the IRB, another 19 never started inclusion, and 10 were still running. Of the 574 trials remaining in the analysis, 334 (58%) were published as peer-reviewed article. The multivariable logistic regression model identified the following determinants with a robust, statistically significant association with publication: phase 2 (60% published; adjusted OR 2.6, 95% CI 1.1-5.9), phase 3 (73% published; adjusted OR 4.1, 95% CI 1.7-10.0), and trials not belonging to phase 1-4 (60% published; adjusted OR 3.2, 95% CI 1.5 to 6.5) compared to phase 1 trials (35% published); trials with a company or investigator as applicant (63% published) compared to trials with a Contract Research Organization (CRO) as applicant (50% published; adjusted OR 1.7; 95% CI 1.1-2.8); and multicenter trials also conducted in other EU countries (68% published; adjusted OR 2.2, 95% CI 1.1-4.4) or also outside the European Union (72% published; adjusted OR 2.0, 95% CI 1.0-4.0) compared to single-center trials (45% published). Trials that were not prospectively registered (48% published) had a lower likelihood of publication compared to prospectively registered trials (75% published; adjusted OR 0.5, 95% CI 0.3-0.8), as well as trials that were terminated early (33% published) compared to trials that were completed as planned (64% published; adjusted OR 0.2, 95% CI 0.1-0.3). The non-publication rate of clinical trials seems to have improved compared to previous inception cohorts, but is still far from optimal, in particular among phase 1, single-center, not prospectively registered, and early terminated trials.


Assuntos
Bibliometria , Ensaios Clínicos Fase I como Assunto , Editoração/estatística & dados numéricos , Algoritmos , Aprovação de Drogas , Avaliação de Medicamentos , Comitês de Ética em Pesquisa , Seguimentos , Humanos , Estimativa de Kaplan-Meier , Análise Multivariada , Países Baixos , Razão de Chances , Revisão por Pares
10.
Curr Med Res Opin ; 32(7): 1269-76, 2016 07.
Artigo em Inglês | MEDLINE | ID: mdl-27009363

RESUMO

AIM: To facilitate a risk-based approach for the supervision of clinical trials on medicinal products, we identified and categorized indicators that may present an elevated safety and/or ethical risk for participants, and/or for data integrity. The indicators are relevant for all stakeholders including participants, regulatory bodies, health care inspectorates, sponsors and trial sites. METHODS: The sources of indicators included Medline (using the search terms risk-based/-triggered/-driven oversight/monitoring/inspection), relevant documents from websites of regulatory authorities in Europe, North America and Australia, and results of a brainstorm session organized for experts working in the field. Indicators were classified according to risk area (safety and ethical, data integrity, or both). RESULTS: In total, we identified 69 risk indicators that were categorized into six branch-levels of the taxonomy. We visualized the taxonomy in a tree structure to clearly distinguish individual indicators. In addition to readily detectable risk indicators, more context-related aspects determine the final impact of the trial and constitute further components in risk assessment. Context-related aspects include potential high media attention, consequences for the reputation of medical research, and the socioeconomic situation in the geographic region and have to be considered on a case-by-case basis. CONCLUSIONS: We identified a wide array of risk indicators for clinical trials on medicinal products and we used a tree structure to incorporate the indicators identified to clearly distinguish individual indicators and to enable efficient use of the indicators. The overview of indicators may facilitate multiple stakeholders in developing structured risk assessment (identification and analysis) for supervising clinical trials on medicinal products. Stakeholders can interpret and prioritize the indicators from their own perspective.


Assuntos
Pesquisa Biomédica , Ensaios Clínicos como Assunto , Pesquisa Biomédica/ética , Pesquisa Biomédica/organização & administração , Pesquisa Biomédica/estatística & dados numéricos , Ensaios Clínicos como Assunto/ética , Ensaios Clínicos como Assunto/organização & administração , Ensaios Clínicos como Assunto/estatística & dados numéricos , Humanos , Fatores de Risco
11.
BMJ Open ; 5(7): e007827, 2015 Jul 07.
Artigo em Inglês | MEDLINE | ID: mdl-26152325

RESUMO

INTRODUCTION: Responsible conduct of research implies that results of clinical trials should be completely and adequately reported. This article describes the design of a cohort study that aims to investigate the occurrence and the determinants of selective reporting in an inception cohort of all clinical drug trials that were reviewed by the Dutch Institutional Review Boards (IRBs) in 2007. It also describes the characteristics of the study cohort. METHODS AND ANALYSIS: In 2007, Dutch IRBs reviewed 622 clinical drug trials. For each trial, we assessed the stages of progress. We discriminated five intermediate stages and five definite stages. Intermediate stages of progress are: approved by an IRB; started inclusion; completed as planned; terminated early; published as article. The definite stages of progress are: rejected by an IRB; never started inclusion; not published as article; completely reported; selectively reported. We will use univariate and multivariate Cox regression models to identify trial characteristics associated with non-publication. We will identify seven trial-specific discrepancy items, including the objectives, inclusion and exclusion criteria, end points, sample size, additional analyses, type of population analysis and sponsor acknowledgement. The percentage of trials with discrepancies between the protocol and the publication will be scored. We will investigate the association between trial characteristics and the occurrence of discrepancies. ETHICS AND DISSEMINATION: No IRB-approval is required for this study. Access to confidential research protocols was provided by the Central Committee on Research Involving Human Subjects. We plan to finish data collection in June 2015, and expect to complete data cleaning, analysis and manuscript preparation within the next 3 months. Hence, a first draft of an article containing the results is expected before the end of October 2015.


Assuntos
Ensaios Clínicos como Assunto/métodos , Preparações Farmacêuticas , Projetos de Pesquisa , Ensaios Clínicos como Assunto/ética , Estudos de Coortes , Ética em Pesquisa , Humanos , Disseminação de Informação/ética , Viés de Publicação , Editoração/ética
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