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1.
Trials ; 23(1): 458, 2022 Jun 02.
Artigo em Inglês | MEDLINE | ID: mdl-35655288

RESUMO

BACKGROUND: At the 2015 REWARD/EQUATOR conference on research waste, the late Doug Altman revealed that his only regret about his 1994 BMJ paper 'The scandal of poor medical research' was that he used the word 'poor' rather than 'bad'. But how much research is bad? And what would improve things? MAIN TEXT: We focus on randomised trials and look at scale, participants and cost. We randomly selected up to two quantitative intervention reviews published by all clinical Cochrane Review Groups between May 2020 and April 2021. Data including the risk of bias, number of participants, intervention type and country were extracted for all trials included in selected reviews. High risk of bias trials was classed as bad. The cost of high risk of bias trials was estimated using published estimates of trial cost per participant. We identified 96 reviews authored by 546 reviewers from 49 clinical Cochrane Review Groups that included 1659 trials done in 84 countries. Of the 1640 trials providing risk of bias information, 1013 (62%) were high risk of bias (bad), 494 (30%) unclear and 133 (8%) low risk of bias. Bad trials were spread across all clinical areas and all countries. Well over 220,000 participants (or 56% of all participants) were in bad trials. The low estimate of the cost of bad trials was £726 million; our high estimate was over £8 billion. We have five recommendations: trials should be neither funded (1) nor given ethical approval (2) unless they have a statistician and methodologist; trialists should use a risk of bias tool at design (3); more statisticians and methodologists should be trained and supported (4); there should be more funding into applied methodology research and infrastructure (5). CONCLUSIONS: Most randomised trials are bad and most trial participants will be in one. The research community has tolerated this for decades. This has to stop: we need to put rigour and methodology where it belongs - at the centre of our science.


Assuntos
Pesquisa Biomédica , Pesquisadores , Emoções , Humanos , Masculino , Projetos de Pesquisa , Recompensa
2.
J Contemp Dent Pract ; 23(1): 37-42, 2022 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-35656655

RESUMO

AIM: The aim of this study was to evaluate the effect of combination of surface treatment using laser along with other modalities of surface treatment on shear bond strength of zirconia to veneering ceramic. MATERIALS AND METHODS: Milled and sintered zirconia cylinders (n = 150) were used in the study which were divided into six groups that were subjected to various surface treatments. Samples in group I were subjected to sandblasting. In group II Laser (Er: YAG) surface treatment was performed. Samples in group III were subjected to sandblasting followed by laser ablation. In group IV laser ablation was carried out followed by liner application, and samples in group V were subjected to laser ablation followed by argon plasma treatment. Instron machine was used to test the shear bond strength (SBS). One-way ANOVA and Bonferroni test were used for statistical analysis. RESULT: Samples in group III showed highest values for SBS followed by groups I, IV, and V with less SBS value for group II. CONCLUSION: Thus, the results conclude the use of combination of surface treatment using laser to be an effective modality to enhance the shear bond strength of zirconia. CLINICAL SIGNIFICANCE: Synergistic surface treatment using laser increases the bond strength of zirconia prosthesis to veneering ceramic improving its clinical longevity.


Assuntos
Cerâmica , Lasers , Análise de Variância , Projetos de Pesquisa , Zircônio
3.
J Contemp Dent Pract ; 23(1): 43-48, 2022 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-35656656

RESUMO

AIM: The aim of this study is to evaluate the shear bond strength of nanohybrid composite resins (NCR) and microhybrid composite resins (MCR) placed over three different dentin replacement materials: SDR-Smart Dentin Replacement™, Biodentine™, and resin-modified glass ionomer cement (RMGIC). METHODS AND MATERIALS: Thirty acrylic blocks (50 mm × 20 mm × 15 mm), each with a central hole, were prepared, which were randomly distributed into three equal groups, each corresponding to one of the three dentin replacement materials-SDR, Biodentine, and RMGIC. The central holes were then filled with these materials. After setting and application of the respective adhesive system, the specimens were further divided into two subgroups each of NCR or MCR. The respective composite material was then applied to the dentin replacement materials using a cylindrical plastic matrix. Shear bond strength was tested on a universal testing machine (Instron 3366), at a crosshead speed of 1.0 mm/minute. RESULTS: SDR attained consistently higher shear bond strength (means: 21.18, 22.19 Mpa) values than RMGIC and Biodentine, with both types of composite resins (MCR and NCR), which were statistically significant (p <0.001). When considering the means of the shear bond strength measurements obtained by the two types of the composite resin, no significant difference (p <0.05) was found between them with all three types of dentin replacement materials. CONCLUSION: There is no significant difference in the bond strengths achieved between MCR and NCR to the different dentine replacement materials. Hence, either type of composite resin may be expected to achieve similar bond strengths to the underlying substrate. SDR™ is a suitable dentine replacement material for placing below a composite resin veneer as it can achieve immediate higher bond strengths. CLINICAL SIGNIFICANCE: SDR can be used as an effective bulk fill material in deep dentinal caries which can be capped with composite resins.


Assuntos
Resinas Compostas , Cimentos de Ionômeros de Vidro , Dentina , Projetos de Pesquisa , Resistência ao Cisalhamento
4.
J Contemp Dent Pract ; 23(1): 61-65, 2022 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-35656659

RESUMO

AIM: Aim of the current research is to establish and assess the microleakage in bulk-fill composite, nanohybrid ormocer-based resins, and nanofilled composite resin core build-up materials employing the dye-penetration technique. MATERIALS AND METHODS: Sixty human mandibular first premolar teeth with a solitary root canal without dental caries were chosen for this research. Each specimen was subjected to decoronation of 2 mm from the cementoenamel junction (CEJ), following which the root canal treatment procedure was rendered complete. A space for the post was made for all the 60 samples. Following positioning of the post, specimens were allocated into one of the following three investigational groups (20 specimens in every group) on the basis of the core build-up materials used as group I: bulk-fill composites, group II: nanohybrid ormocer-based resins, and group III: nanofilled resin composites. Direct composite was used for core build-up and subjected to light-curing. Following this, the specimens were immersed in 1% methylene blue solution for 24 hours interval. Each section was evaluated for dye diffusion employing a stereomicroscope with software at a magnifying power of 40× and surface contact between dentin and base of the material was evaluated under scanning electron microscope. RESULTS: Nanohybrid ormocer-based composites exhibited the least microleakage at 1.12 ± 0.14, in pursuit by nanofilled composite resins at 1.79 ± 0.09, and finally the bulk-fill composites at 2.85 ± 0.11, amid the investigational groups studied. A statistically significant difference amid the three dissimilar cores buildup substances was found upon analysis of variance. CONCLUSION: Despite the study limitations, this research came to a conclusion that each of the three investigated core build-up substances exhibited microleakage. However, amid the three, nanohybrid ormocer-based composites depicted the lowest amount of microleakage in pursuit by the nanofilled resins and the bulk-fill composites. CLINICAL SIGNIFICANCE: Core build-up is an important requirement as the remaining tooth substance following root canal treatment reduces and needs reinforcement with core build-up to sustain the tooth structure and provide resistance. A vital mandate for enduring efficiency of the restoration in the mouth is high-quality adhesive bond of these agents to cavity walls with diminished microleakage.


Assuntos
Resinas Compostas , Cárie Dentária , Humanos , Cerâmicas Modificadas Organicamente , Projetos de Pesquisa , Colo do Dente
5.
BMC Health Serv Res ; 22(1): 770, 2022 Jun 11.
Artigo em Inglês | MEDLINE | ID: mdl-35690766

RESUMO

BACKGROUND: Managing multiple sclerosis (MS) includes different treatment approaches. Rehabilitation is a key strategy in MS for improving functioning, activity and participation. As part of a larger study on overall patient experiences with different treatment approaches, this study aims to give an overview of different patients' experiences and perspectives on inpatient rehabilitation in MS. METHODS: We conducted problem-centered interviews in 50 persons with MS in Germany, of whom most had relapsing-remitting MS. We used the maximum variation sampling method during recruitment. Data were analyzed thematically. RESULTS: As a result of the analysis, three major themes were identified: 1) factors contributing to the decision-making concerning rehabilitation, 2) experience with the rehabilitation setting, 3) benefits of rehabilitation treatments. The treating physicians' attitude had a major impact on the decision to either opt for rehabilitation or not. Setting goals prior to rehabilitation was given a high priority. Exchanging experiences with other persons with MS presented a major benefit from rehabilitation while for some being separated from regular daily life resulted in a more ambiguous attitude ranging from appreciation of escaping daily hassles to substantial behavioral change management. CONCLUSION: Patients reported various experiences in the process of decision-making with regard to rehabilitation. Physicians´ advice, goal setting and the selection of the most suitable rehabilitation clinic were considered most relevant.


Assuntos
Esclerose Múltipla Recidivante-Remitente , Esclerose Múltipla , Alemanha , Humanos , Pesquisa Qualitativa , Projetos de Pesquisa
6.
BMC Res Notes ; 15(1): 203, 2022 Jun 11.
Artigo em Inglês | MEDLINE | ID: mdl-35690782

RESUMO

The rising rate of preprints and publications, combined with persistent inadequate reporting practices and problems with study design and execution, have strained the traditional peer review system. Automated screening tools could potentially enhance peer review by helping authors, journal editors, and reviewers to identify beneficial practices and common problems in preprints or submitted manuscripts. Tools can screen many papers quickly, and may be particularly helpful in assessing compliance with journal policies and with straightforward items in reporting guidelines. However, existing tools cannot understand or interpret the paper in the context of the scientific literature. Tools cannot yet determine whether the methods used are suitable to answer the research question, or whether the data support the authors' conclusions. Editors and peer reviewers are essential for assessing journal fit and the overall quality of a paper, including the experimental design, the soundness of the study's conclusions, potential impact and innovation. Automated screening tools cannot replace peer review, but may aid authors, reviewers, and editors in improving scientific papers. Strategies for responsible use of automated tools in peer review may include setting performance criteria for tools, transparently reporting tool performance and use, and training users to interpret reports.


Assuntos
Políticas Editoriais , Revisão da Pesquisa por Pares , Projetos de Pesquisa , Relatório de Pesquisa
7.
Spat Spatiotemporal Epidemiol ; 41: 100506, 2022 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-35691640

RESUMO

This study tested spatio-temporal model prediction accuracy and concurrent validity of observed neighborhood physical disorder collected from virtual audits of Google Street View streetscapes. We predicted physical disorder from spatio-temporal regression Kriging models based on measures at three dates per each of 256 streestscapes (n = 768 data points) across an urban area. We assessed model internal validity through cross validation and external validity through Pearson correlations with respondent-reported perceptions of physical disorder from a breast cancer survivor cohort. We compared validity among full models (both large- and small-scale spatio-temporal trends) versus large-scale only. Full models yielded lower prediction error compared to large-scale only models. Physical disorder predictions were lagged at uniform distances and dates away from the respondent-reported perceptions of physical disorder. Correlations between perceived and observed physical disorder predicted from the full model were higher compared to that of the large-scale only model, but only at locations and times closest to the respondent's exact residential address and questionnaire date. A spatio-temporal Kriging model of observed physical disorder is valid.


Assuntos
Projetos de Pesquisa , Características de Residência , Coleta de Dados , Humanos , Análise Espacial , Caminhada
8.
Spat Spatiotemporal Epidemiol ; 41: 100462, 2022 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-35691644

RESUMO

Spatial and spatio-temporal cluster detection are important tools in public health and many other areas of application. Cluster detection can be approached as a multiple testing problem, typically using a space and time scan statistic. We recast the spatial and spatio-temporal cluster detection problem in a high-dimensional data analytical framework with Poisson or quasi-Poisson regression with the Lasso penalty. We adopt a fast and computationally-efficient method using a novel sparse matrix representation of the effects of potential clusters. The number of clusters and tuning parameters are selected based on (quasi-)information criteria. We evaluate the performance of our proposed method including the false positive detection rate and power using a simulation study. Application of the method is illustrated using breast cancer incidence data from three prefectures in Japan.


Assuntos
Saúde Pública , Projetos de Pesquisa , Análise por Conglomerados , Simulação por Computador , Humanos , Incidência , Análise Espaço-Temporal
9.
Eur J Gen Pract ; 28(1): 136-141, 2022 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-35666561

RESUMO

The European General Practice Research Network (EGPRN) has recently published an updated research strategy with the overall aim being to promote relevant research of the highest quality within general practice/family medicine (GP/FM). The Research Strategy indicates a global direction and serves as a basis for more detailed plans in individual countries that will take into account the characteristics of a country, its specific needs and the level of current research capacity. This paper aims to provide a summary of the EGPRN Research Strategy.The Research Strategy suggests that it is necessary to consider what the knowledge deficits are and to set research priorities. Research capacity building (RCB) is required at all levels. Research in GP/FM will also have to reflect the changes in the profession. An innovative and sustainable-oriented approach to conducting research is needed. Use of existing toolkits and engagement with patient platforms and representative groups are necessary to ensure meaningful user involvement. Knowledge transfer and exchange (KTE) is an important component to ensure a process of exchange between researchers and knowledge users.Working to improve leadership, to support the creation of a research culture in GP/FM and to increase national and international networking are considered as fundamental to ensuring a portfolio of high-quality research and for improving the impact of GP/FM research. The recommendations in the Research Strategy are based on a review of the literature on general practice research from 2010 to 2019 and are set in the context of a theoretical framework.


Assuntos
Medicina de Família e Comunidade , Medicina Geral , Fortalecimento Institucional , Europa (Continente) , Humanos , Projetos de Pesquisa
10.
BMJ Open ; 12(6): e059991, 2022 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-35705341

RESUMO

INTRODUCTION: In Africa, the prevalence of mental health problems is higher among university students than in the general population. A number of systematic reviews and recent prevalence studies have focused on prevalence of mental health issues among college. This mixed-methods systematic review, including meta-analysis and meta-synthesis, will explore: what mental health services are available to university students; the extent to which students access available services and factors associated with service access; and the degree to which students activate (use) accessible services and factors associated with service activation. METHODS AND ANALYSIS: We will conduct electronic literature search of the following databases: PubMed, Cochrane Library, Semantic Scholar, ERIC, Trip Database, Medline and PsycINFO. Disagreement, if any, will be resolved by a third reviewer. Two reviewers will independently assess the methodological quality of included studies using relevant tools. For cross-sectional studies, we will use the Joanna Briggs Institute Checklist for Analytical Cross Sectional Studies whereas qualitative or mixed-methods studies will be assessed using the Critical Appraisal Skills Programme. OR, risk ratio or mean difference with 95% CI will be considered as the effect size. We will assess heterogeneity between studies by appropriate subgroup analyses. Publication bias will be detected using funnel plots. ETHICS AND DISSEMINATION: Ethical clearance is not required as we are not collecting primary data. Findings will be disseminated via relevant scientific conferences and peer-reviewed publications. PROSPERO REGISTRATION NUMBER: CRD42022296870.


Assuntos
Serviços de Saúde Mental , Projetos de Pesquisa , África/epidemiologia , Estudos Transversais , Humanos , Metanálise como Assunto , Estudantes , Revisões Sistemáticas como Assunto , Universidades
11.
BMJ Open ; 12(6): e061185, 2022 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-35705347

RESUMO

INTRODUCTION: Knowledge translation platforms (KTPs) are intermediary organisations, initiatives or networks whose intent is to bridge the evidence into action divide. Strategies and tools include collaborative knowledge production, capacity building, information exchange and dialogue to facilitate relevant and timely engagement between researchers and decision-makers and other relevant stakeholders. With the wide range of definitions and descriptions of KTPs, there is a need to (1) provide a nuanced understanding of characteristics of KTPs and (2) assess and consolidate research methods used in mapping and evaluating KTPs to inform standardised process and impact evaluation. METHODS AND ANALYSIS: This scoping review will follow the recommended and accepted methods for scoping reviews and reporting guidelines. Eligibility for inclusion is any conceptual or empirical health-related qualitative, quantitative and/or mixed method studies including (1) definitions, descriptions and models or frameworks of KTPs (including those that do not self-identify as KTPs, eg, university research centres) and (2) research methods for mapping and/or evaluating KTPs. Searches will be carried out in PubMed, Scopus, CINAHL, Embase, Global Health and Web of Science using a predetermined search strategy, without any date, language or geographical restrictions. Two reviewers will independently screen titles and abstracts. One reviewer will complete data extraction for all included studies, and another will check a sample of 50% of the included studies. The analysis and synthesis will provide (1) an understanding of the various characteristics of KTPs; (2) insight into characteristics or factors that make them resilient and/or adaptive to facilitate impact (ie, influence policy and practice); and (3) an overview of the various methods for mapping and evaluating KTPs. We will explore enhancing an existing framework for classifying KTPs, or perhaps even developing a new framework for identifying and monitoring KTPs if necessary and relevant. ETHICS AND DISSEMINATION: This scoping review does not require ethics approval, as we will only include information from previously conducted studies and we will not involve human participants. The results will be submitted to a peer-reviewed scientific journal for publication and as conference presentations.


Assuntos
Projetos de Pesquisa , Humanos , Conhecimento , Literatura de Revisão como Assunto
12.
Artigo em Inglês | MEDLINE | ID: mdl-35682157

RESUMO

The rational allocation of spatial resources is an important factor to ensure the sustainable development of rural areas, and effective pre-emptive spatial evaluation is the prerequisite for identifying the predicament of rural resource allocation. Multi-criteria decision-making analysis has advantages in solving multi-attribute and multi-objective decision-making problems, and has been used in sustainability evaluation research in various disciplines in recent years. Previous studies have proved the value of spatial evaluation using multi-criteria decision analysis in guiding rural incremental development and inventory updates, but systematic reviews of the previous literature from a multidisciplinary perspective and studies of the implementation steps of the evaluation framework are lacking. In the current paper, the research is reviewed from the two levels of quantitative statistics and research content, and through vertical and horizontal comparisons based on three common operating procedures: standard formulation, weight distribution, and ranking and verification. Through the results, the application status and characteristics of the MCDA method in related research are determined, and five research foci in the future are proposed.


Assuntos
Tomada de Decisões , Técnicas de Apoio para a Decisão , Projetos de Pesquisa
13.
Artigo em Inglês | MEDLINE | ID: mdl-35682246

RESUMO

Under the background of global environmental change, a huge impact has been made on the village ecosystem, which leads to disorder of structure and function of the village ecosystem. The current management measures of the village have failed in allowing the village to achieve sustainable development. Research on the vulnerability and resilience of the village ecosystem is helpful in regards to the ecological restoration of the village. The research status and progress in regards to the vulnerability and resilience of the village ecosystem are not clear, and the summary of research results and problems is insufficient. Based on 87 related literatures, this paper focuses on the current status and progress of village ecosystem vulnerability and resilience research, and reveals the current research results and shortcomings of village ecosystem vulnerability and resilience. We found that: (1) the research on vulnerability and resilience of the village ecosystem is on the rise; (2) the research mainly focuses on the index system, monitoring and assessment, mechanism research and strategy research. The monitoring and assessment research is the most prominent, which mainly discusses the research methods, the vulnerability and the resilience of the village ecosystem; (3) the study area is mainly concentrated in Asia, North America and Africa. Research institutions are mainly institutions of higher learning and research institutes (centers). Finally, this paper finds that major scientific and technical studies such as the construction of indicator systems and the study of governance strategies in the study of vulnerability and resilience of village ecosystems are lagging behind. In future research, we should deepen the research on the concept and connotation of vulnerability and resilience. We must establish a scientific and reasonable research framework for vulnerability and resilience of the village ecosystem. We should also strengthen and improve the index system of vulnerability and resilience of the village ecosystem. We should strengthen research on the impact mechanisms and governance strategies of vulnerability and resilience, and apply the research on vulnerability and resilience to the planning and governance of the village ecosystem.


Assuntos
Conservação dos Recursos Naturais , Ecossistema , África , Ásia , Conservação dos Recursos Naturais/métodos , Projetos de Pesquisa
14.
Trials ; 23(1): 485, 2022 Jun 13.
Artigo em Inglês | MEDLINE | ID: mdl-35698096

RESUMO

BACKGROUND: Neurogenic bladder (NGB) is a chronic and disabling condition with a high prevalence rate, which can cause economic burden on patients and their families and reduce the quality of life of patients. Researchers have carried out a large number of clinical trials on the effectiveness and safety of different interventions for the treatment of NGB. The published clinical trials of NGB generally suffered from inconsistent and irregular reporting of outcome indicators. To facilitate future research studies of NGB, a core outcome set (COS) is required, which helps translate the results into high-quality evidence. METHODS AND ANALYSIS: This mixed-method project has four phases instrument: in phase 1, a scoping review of the literature to identify outcomes that have been reported in clinical trials and systematic reviews of clinical trials of interventions for NGB; in phase 2, a qualitative component using interviews to obtain the views of NGB patients, families, and their caregivers; in phase 3, Delphi survey among stakeholders to prioritize the core outcomes; and in phase 4, a face-to-face consensus meeting to discuss and agree on the final NBG COS. CONCLUSIONS: We will develop a COS that should be reported in future clinical trials of NGB. TRIAL REGISTRATION: Core Outcome Measures in Effectiveness Trials (COMET) Initiative database registration: http://www.comet-initiative.org/studies/details/1985 . Registered on 02 January 2022. INPLASY  INPLASY202210007.


Assuntos
Qualidade de Vida , Bexiga Urinaria Neurogênica , Técnica Delfos , Determinação de Ponto Final , Humanos , Avaliação de Resultados em Cuidados de Saúde/métodos , Projetos de Pesquisa , Literatura de Revisão como Assunto , Resultado do Tratamento , Bexiga Urinaria Neurogênica/diagnóstico , Bexiga Urinaria Neurogênica/terapia
16.
BMC Med Res Methodol ; 22(1): 152, 2022 May 28.
Artigo em Inglês | MEDLINE | ID: mdl-35643430

RESUMO

BACKGROUND: Observational data are increasingly being used to conduct external comparisons to clinical trials. In this study, we empirically examined whether different methodological approaches to longitudinal missing data affected study conclusions in this setting. METHODS: We used data from one clinical trial and one prospective observational study, both Norwegian multicenter studies including patients with recently diagnosed rheumatoid arthritis and implementing similar treatment strategies, but with different stringency. A binary disease remission status was defined at 6, 12, and 24 months in both studies. After identifying patterns of longitudinal missing outcome data, we evaluated the following five approaches to handle missingness: analyses of patients with complete follow-up data, multiple imputation (MI), inverse probability of censoring weighting (IPCW), and two combinations of MI and IPCW. RESULTS: We found a complex non-monotone missing data pattern in the observational study (N = 328), while missing data in the trial (N = 188) was monotone due to drop-out. In the observational study, only 39.0% of patients had complete outcome data, compared to 89.9% in the trial. All approaches to missing data indicated favorable outcomes of the treatment strategy in the trial and resulted in similar study conclusions. Variations in results across approaches were mainly due to variations in estimated outcomes for the observational data. CONCLUSIONS: Five different approaches to handle longitudinal missing data resulted in similar conclusions in our example. However, the extent and complexity of missing observational data affected estimated comparative outcomes across approaches, highlighting the need for careful consideration of methods to account for missingness in this setting. Based on this empirical examination, we recommend using a prespecified advanced missing data approach to account for longitudinal missing data, and to conduct alternative approaches in sensitivity analyses.


Assuntos
Modelos Estatísticos , Projetos de Pesquisa , Grupos Controle , Humanos , Probabilidade
17.
BMC Med Res Methodol ; 22(1): 153, 2022 May 28.
Artigo em Inglês | MEDLINE | ID: mdl-35643435

RESUMO

BACKGROUND: As the cost of RNA-sequencing decreases, complex study designs, including paired, longitudinal, and other correlated designs, become increasingly feasible. These studies often include multiple hypotheses and thus multiple degree of freedom tests, or tests that evaluate multiple hypotheses jointly, are often useful for filtering the gene list to a set of interesting features for further exploration while controlling the false discovery rate. Though there are several methods which have been proposed for analyzing correlated RNA-sequencing data, there has been little research evaluating and comparing the performance of multiple degree of freedom tests across methods. METHODS: We evaluated 11 different methods for modelling correlated RNA-sequencing data by performing a simulation study to compare the false discovery rate, power, and model convergence rate across several hypothesis tests and sample size scenarios. We also applied each method to a real longitudinal RNA-sequencing dataset. RESULTS: Linear mixed modelling using transformed data had the best false discovery rate control while maintaining relatively high power. However, this method had high model non-convergence, particularly at small sample sizes. No method had high power at the lowest sample size. We found a mix of conservative and anti-conservative behavior across the other methods, which was influenced by the sample size and the hypothesis being evaluated. The patterns observed in the simulation study were largely replicated in the analysis of a longitudinal study including data from intensive care unit patients experiencing cardiogenic or septic shock. CONCLUSIONS: Multiple degree of freedom testing is a valuable tool in longitudinal and other correlated RNA-sequencing experiments. Of the methods that we investigated, linear mixed modelling had the best overall combination of power and false discovery rate control. Other methods may also be appropriate in some scenarios.


Assuntos
RNA , Projetos de Pesquisa , Humanos , Estudos Longitudinais , RNA/genética , Tamanho da Amostra , Análise de Sequência de RNA/métodos
18.
BMJ ; 377: e067745, 2022 06 10.
Artigo em Inglês | MEDLINE | ID: mdl-35688481

RESUMO

OBJECTIVE: To describe an approach for reporting master protocol research programs (MPRPs) that is consistent with existing good reporting practices and that uses structured information to convey the overall master protocol and design of each substudy. DESIGN: Qualitative analysis. DATA SOURCES: ClinicalTrials.gov trial registry. MAIN OUTCOME MEASURES: Established goals and related practices of the trial reporting system were outlined, examples and key characteristics of MPRPs were reviewed, and specific challenges in registering and reporting summary results to databases designed for traditional clinical trial designs that rely on a model of one study per protocol were identified. RESULTS: A reporting approach is proposed that accommodates the complex study design of MPRPs and their results. This approach involves the use of separate registration records for each substudy within one MPRP protocol (with potential exceptions noted). CONCLUSIONS: How the proposed approach allows for clear, descriptive, structured information about each substudy's prespecified design and supports timely reporting of results after completion of each substudy is described and illustrated. Although the focus is on reporting to ClinicalTrials.gov, the approach supports broader application across trial registries and results databases. This paper is intended to stimulate further discussion of this approach among stakeholders, build awareness about the need to improve reporting of MPRPs, and encourage harmonization across trial registries globally.


Assuntos
Ensaios Clínicos como Assunto , Projetos de Pesquisa , Bases de Dados Factuais , Humanos , Pesquisa Qualitativa , Sistema de Registros
19.
JNCI Cancer Spectr ; 6(1)2022 Jan 05.
Artigo em Inglês | MEDLINE | ID: mdl-35699499

RESUMO

When designing a comparative oncology trial for an overall or progression-free survival endpoint, investigators often quantify the treatment effect using a difference in median survival times. However, rather than directly designing the study to estimate this difference, it is almost always converted to a hazard ratio (HR) to determine the study size. At the analysis stage, the hazard ratio is utilized for formal analysis, yet because it may be difficult to interpret clinically, especially when the proportional hazards assumption is not met, the observed medians are also reported descriptively. The hazard ratio and median difference contrast different aspects of the survival curves. Whereas the hazard ratio places greater emphasis on late-occurring separation, the median difference focuses locally on the centers of the distributions and cannot capture either short- or long-term differences. Having 2 sets of summaries (a hazard ratio and the medians) may lead to incoherent conclusions regarding the treatment effect. For instance, the hazard ratio may suggest a treatment difference whereas the medians do not, or vice versa. In this commentary, we illustrate these commonly encountered issues using examples from recent oncology trials. We present a coherent alternative strategy that, unlike relying on the hazard ratio, does not require modeling assumptions and always results in clinically interpretable summaries of the treatment effect.


Assuntos
Neoplasias , Projetos de Pesquisa , Humanos , Oncologia , Neoplasias/terapia , Modelos de Riscos Proporcionais
20.
BMJ Open ; 12(6): e057289, 2022 Jun 14.
Artigo em Inglês | MEDLINE | ID: mdl-35701049

RESUMO

INTRODUCTION: The global incidence of patients with type 2 diabetes mellitus (T2DM) with dry eye is increasing annually, which imposes additional healthcare costs and financial burden on families and societies. In clinical practice, artificial tears are often used for symptomatic treatment, but these can only relieve the symptoms of discomfort. Acupuncture is a widely used alternative therapy. Indeed, randomised trials have found that acupuncture confers a definite therapeutic effect on patients with T2DM with dry eye. However, systematic reviews on the effectiveness and safety of acupuncture are lacking, therefore this systematic review aims to evaluate the effectiveness and safety of acupuncture for T2DM with dry eye. METHODS AND ANALYSIS: Four English databases (PubMed, Cochrane Library, Embase and Ovid), three Chinese databases (China National Knowledge Infrastructure, Wanfang, Chonqing VIP Information), three Japanese databases (Japan Science, Technology Agency and Japan Medical Abstracts Society) and three Korean databases (Korean Medical database, Oriental Medicine Advanced Searching Integrated System and Research Information Service System) will be searched for reports published between 1 January 2007 and 1 October 2021. Only randomised controlled trials will be included, and language or publication dates will not be restricted. Two researchers will independently extract, manage and analyse data. The primary outcomes will include Schirmer's I test, breakup time, corneal fluorescein staining and ocular surface disease index scores. Secondary results will include visual analogue scale scores for ocular symptoms and any adverse events related to acupuncture. We will use Review Manager V.5.4 for the meta-analysis. The risk of bias will be independently assessed using Cochrane's 'risk of bias' tool. ETHICS AND DISSEMINATION: Ethical approval will not be required since raw data will not be collected or generated. Our findings will be disseminated through peer-reviewed journal. PROSPERO REGISTRATION NUMBER: CRD42021271891.


Assuntos
Terapia por Acupuntura , Diabetes Mellitus Tipo 2 , Síndromes do Olho Seco , Terapia por Acupuntura/métodos , Diabetes Mellitus Tipo 2/complicações , Diabetes Mellitus Tipo 2/terapia , Síndromes do Olho Seco/terapia , Humanos , Metanálise como Assunto , Projetos de Pesquisa , Revisões Sistemáticas como Assunto
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