457 research outputs found

    Surrogate endpoints in trials-a call for better reporting

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    Better reporting of RCTs with primary surrogate endpoints

    Decision uncertainty and value of further research: a case-study in fenestrated endovascular aneurysm repair for complex abdominal aortic aneurysms

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    Background: Fenestrated endovascular aneurysm repair (fEVAR) is a new approach for complex abdominal aortic aneurysms, limited to a few specialist centers, with limited evidence base. We developed a cost-effectiveness decision model of fEVAR compared to open surgical repair (OSR) to investigate the likely direction of costs and benefits and inform further research projects on this technology. Methods: A systematic review with meta-analysis and a four-state Markov model were used to estimate the cost-effectiveness of fEVAR versus OSR. We used a recent coverage with evidence development framework to characterize the main sources of uncertainty and inform decisions about the type of further research that would be most worthwhile and feasible. Results: Seven observational comparative studies were identified, of which four presented odds ratios adjusted for confounders. The odds ratios for operative mortality varied widely between studies. Assuming a central estimate of the odds ratio of 0.54 (95% CI 0.05–6.24), the decision model estimated that the incremental cost per quality adjusted life year (QALY) was £74,580/QALY with a probability of 9 and 16% of being cost-effective at standard cost-effectiveness thresholds of £20,000/QALY and £30,000/QALY, respectively. The Expected Value of Perfect Information over 10 years at a threshold of £20,000/QALY was £11.2 million. Operative mortality contributed to most of the uncertainty in the decision model. Conclusions: In the case of “maturing technologies”, decision modelling indicates the likely direction of costs and benefits and guides the development of further research projects. In our analysis of fEVAR versus OSR, decision uncertainty, particularly around operative mortality, might be effectively resolved by a short-term RCT, or possibly a well-conducted comparative observational study. Decision makers may consider that a conditional coverage decision is warranted with assessments required to make this type of recommendation depending on local priorities and circumstances

    Structural studies of cerebral cavernous malformations 2 (CCM2) reveal a folded helical domain at its C-terminus

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    AbstractCerebral cavernous malformations (CCM) are neurovascular dysplasias affecting up to 0.5% of the population. Mutations in the CCM2 gene are associated with acquisition of CCM. We identify a previously uncharacterized domain at the C-terminus of CCM2 and determine its 1.9Å resolution crystal structure. Because this domain is structurally homologous to the N-terminal domain of harmonin, we name it the CCM2 harmonin-homology domain or HHD. CCM2 HHD is observed in two conformations, and we employ analytical ultracentrifugation to test its oligomerization. Additionally, CCM2 HHD contains an unusually long 13-residue 310 helix. This study provides the first structural characterization of CCM2.Structured summary of protein interactionsCCM2 binds to CCM3 by pull down (View interaction)CCM2 and CCM2 bind by X-ray crystallography (View interaction)CCM2 and CCM2 bind by molecular sieving (View interaction

    Comparison of treatment effect sizes from pivotal and postapproval trials of novel therapeutics approved by the FDA based on surrogate markers of disease: a meta-epidemiological study

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    Background: The U.S. Food and Drug Administration (FDA) often approves new drugs based on trials that use surrogate markers for endpoints, which involve certain trade-offs and may risk making erroneous inferences about the medical product’s actual clinical effect. This study aims to compare the treatment effects among pivotal trials supporting FDA approval of novel therapeutics based on surrogate markers of disease with those observed among postapproval trials for the same indication. Methods: We searched Drugs@FDA and PubMed to identify published randomized superiority design pivotal trials for all novel drugs initially approved by the FDA between 2005 and 2012 based on surrogate markers as primary endpoints and published postapproval trials using the same surrogate markers or patient-relevant outcomes as endpoints. Summary ratio of odds ratios (RORs) and difference between standardized mean differences (dSMDs) were used to quantify the average difference in treatment effects between pivotal and matched postapproval trials. Results: Between 2005 and 2012, the FDA approved 88 novel drugs for 90 indications based on one or multiple pivotal trials using surrogate markers of disease. Of these, 27 novel drugs for 27 indications were approved based on pivotal trials using surrogate markers as primary endpoints that could be matched to at least one postapproval trial, for a total of 43 matches. For nine (75.0%) of the 12 matches using the same non-continuous surrogate markers as trial endpoints, pivotal trials had larger treatment effects than postapproval trials. On average, treatment effects were 50% higher (more beneficial) in the pivotal than the postapproval trials (ROR 1.5; 95% confidence interval CI 1.01–2.23). For 17 (54.8%) of the 31 matches using the same continuous surrogate markers as trial endpoints, pivotal trials had larger treatment effects than the postapproval trials. On average, there was no difference in treatment effects between pivotal and postapproval trials (dSMDs 0.01; 95% CI -0.15–0.16). Conclusions: Many postapproval drug trials are not directly comparable to previously published pivotal trials, particularly with respect to endpoint selection. Although treatment effects from pivotal trials supporting FDA approval of novel therapeutics based on non-continuous surrogate markers of disease are often larger than those observed among postapproval trials using surrogate markers as trial endpoints, there is no evidence of difference between pivotal and postapproval trials using continuous surrogate markers

    Meta-analyses of randomized controlled trials show suboptimal validity of surrogate outcomes for overall survival in advanced colorectal cancer

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    Objectives: To quantify and compare the treatment effects on three surrogate end points, progression-free survival (PFS), time to progression (TTP), and tumor response rate (TR) vs. overall survival (OS) based on a meta-analysis of randomized controlled trials (RCTs) of drug interventions in advanced colorectal cancer (aCRC). Study Design and Setting: We systematically searched for RCTs of pharmacologic therapies in aCRC between 2003 and 2013. Trial characteristics, risk of bias, and outcomes were recorded based on a predefined form. Univariate and multivariate random-effects meta-analyses were used to estimate pooled summary treatment effects. The ratio of hazard ratios (HRs)/odds ratios (ORs) and difference in medians were used to quantify the degree of difference in treatment effects on the surrogate end points and OS. Spearman ρ, surrogate threshold effect (STE), and R2 were also estimated across predefined trial-level covariates. Results: We included 101 RCTs. In univariate and multivariate meta-analyses, we found larger treatment effects for the surrogates than for OS. Compared with OS, treatment effects were on average 13% higher when HRs were measured and 3% to 45% higher when ORs were considered; differences in median PFS/TTP were higher than on OS by an average of 0.5 month. Spearman ρ ranged from 0.39 to 0.80, mean R2 from 0.06 to 0.65, and STE was 0.8 for HRPFS, 0.64 for HRTTP, or 0.28 for ORTR. The stratified analyses revealed high variability across all strata. Conclusion: None of the end points in this study were found to achieve the level of evidence (ie, mean R2trial > 0.60) that has been set to select high or excellent correlation levels by common surrogate evaluation tools. Previous surrogacy relationships observed between PFS and TTP vs. OS in selected settings may not apply across other classes or lines of therapy

    Development of a framework and decision tool for the evaluation of health technologies based on surrogate endpoint evidence

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    In the drive toward faster patient access to treatments, health technology assessment (HTA) agencies and payers are increasingly faced with reliance on evidence based on surrogate endpoints, increasing decision uncertainty. Despite the development of a small number of evaluation frameworks, there remains no consensus on the detailed methodology for handling surrogate endpoints in HTA practice. This research overviews the methods and findings of four empirical studies undertaken as part of COMED (Pushing the Boundaries of Cost and Outcome Analysis of Medical Technologies) program work package 2 with the aim of analyzing international HTA practice of the handling and considerations around the use of surrogate endpoint evidence. We have synthesized the findings of these empirical studies, in context of wider contemporary body of methodological and policy-related literature on surrogate endpoints, to develop a web-based decision tool to support HTA agencies and payers when faced with surrogate endpoint evidence. Our decision tool is intended for use by HTA agencies and their decision-making committees together with the wider community of HTA stakeholders (including clinicians, patient groups, and healthcare manufacturers). Having developed this tool, we will monitor its use and we welcome feedback on its utility

    POLA GAYA HIDUP DALAM KEUANGAN KELUARGA (STUDI KASUS:UNIT KERJA INSTITUSI PENDIDIKAN SWASTA DI BANDUNG)

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    This research was conducted to determine lifestyle patterns in family finances. This research was conducted in a private educational institution in Bandung. Data collection technique used in this research is survey technique with questionnaires and for data analysis technique that used in this study is descriptive analysis. It has been found that the lifestyle patterns of employees at one of private educational institution in Bandung generally still have a good patterns.This is proved by the monetary sequences of their revenue and expense. Also, the priority selection of their needs and wants in fullfilling their life style is still in control.The result of this research, generally the respondents already have their own house, vehicles, and mobile communication devices like handphone, with purchasing frequency in 1 year mostly less than 2 times.Moreover, the respondents also already have a habit of saving/investing and insurance.T o fill their spare time, respondents prefer to gather with their family, go to mall with frequency in a month 1-4 times and also they do exercise. But, the problem that needs to be taken care of is how to handle their credit card/loans because a lot of respondents have routine spending of paying credit card installment/loans.From this research, also found that there is still a lack of awareness for making simple bookkeeping of their revenue and expense. Therefore to make them literate family finances, they need to follow a counseling and training about family finances. Even, they are suggested to follow the counseling and training with their family members

    APFELE, una herramienta para contar puntos función basada en el enfoque de estimación del tamaño funcional del software en la etapa de elicitación de requerimientos

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    La aplicación del Análisis de Puntos Función en la etapa inicial del desarrollo de sistemas de software permite obtener una medición del tamaño del producto a construir sin depender del lenguaje y la tecnología que se utilizarán. Esto permite estimar costos, esfuerzo y duración antes de avanzar en el proceso de desarrollo de un proyecto. La medición de Puntos Función puede aplicarse a los escenarios generados en la etapa de Elicitación de Requerimientos. En este artículo se presenta la herramienta CASE APFELE semi-automática integrada, desarrollada para soportar el proceso de medición de los escenarios, que permitió sustituir los distintos utilitarios necesarios para implementar “manualmente” la medición, presentar y documentar sus resultados, aprovechando la ventaja del hipertexto lográndose así una importante reducción en el tiempo y energía requeridos para obtener la mé trica de funcionalidad de un proyecto de software en su etapa inicial.Eje: Ingeniería de Software y Base de DatosRed de Universidades con Carreras en Informática (RedUNCI
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