48 research outputs found
Accurate prediction of kinase-substrate networks using knowledge graphs
Phosphorylation of specific substrates by protein kinases is a key control mechanism for vital cell-fate decisions and other cellular processes. However, discovering specific kinase-substrate relationships is time-consuming and often rather serendipitous. Computational predictions alleviate these challenges, but the current approaches suffer from limitations like restricted kinome coverage and inaccuracy. They also typically utilise only local features without reflecting broader interaction context. To address these limitations, we have developed an alternative predictive model. It uses statistical relational learning on top of phosphorylation networks interpreted as knowledge graphs, a simple yet robust model for representing networked knowledge. Compared to a representative selection of six existing systems, our model has the highest kinome coverage and produces biologically valid high-confidence predictions not possible with the other tools. Specifically, we have experimentally validated predictions of previously unknown phosphorylations by the LATS1, AKT1, PKA and MST2 kinases in human. Thus, our tool is useful for focusing phosphoproteomic experiments, and facilitates the discovery of new phosphorylation reactions. Our model can be accessed publicly via an easy-to-use web interface (LinkPhinder).Phosphorylation of specific substrates by protein kinases is a key control mechanism for vital cell-fate decisions and other cellular processes. However, discovering specific kinase-substrate relationships is time-consuming and often rather serendipitous. Computational predictions alleviate these challenges, but the current approaches suffer from limitations like restricted kinome coverage and inaccuracy. They also typically utilise only local features without reflecting broader interaction context. To address these limitations, we have developed an alternative predictive model. It uses statistical relational learning on top of phosphorylation networks interpreted as knowledge graphs, a simple yet robust model for representing networked knowledge. Compared to a representative selection of six existing systems, our model has the highest kinome coverage and produces biologically valid high-confidence predictions not possible with the other tools. Specifically, we have experimentally validated predictions of previously unknown phosphorylations by the LATS1, AKT1, PKA and MST2 kinases in human. Thus, our tool is useful for focusing phosphoproteomic experiments, and facilitates the discovery of new phosphorylation reactions. Our model can be accessed publicly via an easy-to-use web interface (LinkPhinder)
European expert recommendations on clinical investigation and evaluation of high‐risk medical devices for children
Several high-risk medical devices for children have become unavailable in the European Union (EU), since requirements and costs for device certification increased markedly due to the EU Medical Device Regulation. The EU-funded CORE-MD project held a workshop in January 2023 with experts from various child health specialties, representatives of European paediatric associations, a regulatory authority and the European Commission Directorate General Health and Food Safety. A virtual follow-up meeting took place in March 2023. We developed recommendations for investigation of high-risk medical devices for children building on participants' expertise and results of a scoping review of clinical trials on high-risk medical devices in children. Approaches for evaluating and certifying high-risk medical devices for market introduction are proposed
The use of clinical study reports to enhance the quality of systematic reviews: a survey of systematic review authors
Background: Clinical study reports (CSRs) are produced for marketing authorisation applications. They often
contain considerably more information about, and data from, clinical trials than corresponding journal publications. Use
of data from CSRs might help circumvent reporting bias, but many researchers appear to be unaware of their existence
or potential value. Our survey aimed to gain insight into the level of familiarity, understanding and use of CSRs, and to
raise awareness of their potential within the systematic review community. We also aimed to explore the potential
barriers faced when obtaining and using CSRs in systematic reviews.
Methods: Online survey of systematic reviewers who (i) had requested or used CSRs, (ii) had considered but not used
CSRs and (iii) had not considered using CSRs was conducted. Cochrane reviewers were contacted twice via
the Cochrane monthly digest. Non-Cochrane reviewers were reached via journal and other website postings.
Results: One hundred sixty respondents answered an open invitation and completed the questionnaire; 20/
160 (13%) had previously requested or used CSRs and other regulatory documents, 7/160 (4%) had considered but not
used CSRs and 133/160 (83%) had never considered this data source. Survey respondents mainly sought data from the
European Medicines Agency (EMA) and/or the Food and Drug Administration (FDA). Motivation for using CSRs
stemmed mainly from concerns about reporting bias 11/20 (55%), specifically outcome reporting bias 11/20
(55%) and publication bias 5/20 (25%). The barriers to using CSRs noted by all types of respondents included
current limited access to these documents (43 respondents), the time and resources needed to obtain and
include these data in evidence syntheses (n = 25) and lack of guidance about how to use these sources in
systematic reviews (n = 26).
Conclusions: Most respondents (irrespective of whether they had previously used them) agreed that access
to CSRs is important, and suggest that further guidance on how to use and include these data would help
to promote their use in future systematic reviews. Most respondents who received CSRs considered them to
be valuable in their systematic review and/or meta-analysis
Publication Bias in Antipsychotic Trials: An Analysis of Efficacy Comparing the Published Literature to the US Food and Drug Administration Database
A comparison of data held by the U.S. Food and Drug Administration (FDA) against data from journal reports of clinical trials enables estimation of the extent of publication bias for antipsychotics
Negative pressure wound therapy: Potential publication bias caused by lack of access to unpublished study results data
<p>Abstract</p> <p>Background</p> <p>Negative pressure wound therapy (NPWT) is widely applied, although the evidence base is weak. Previous reviews on medical interventions have shown that conclusions based on published data alone may no longer hold after consideration of unpublished data. The main objective of this study was to identify unpublished randomised controlled trials (RCTs) on NPWT within the framework of a systematic review.</p> <p>Methods</p> <p>RCTs comparing NPWT with conventional wound therapy were identified using MEDLINE, EMBASE, CINAHL and The Cochrane Library. Every database was searched from inception to May 2005. The search was updated in December 2006. Reference lists of original articles and systematic reviews, as well as congress proceedings and online trial registers, were screened for clues to unpublished RCTs. Manufacturers of NPWT devices and authors of conference abstracts were contacted and asked to provide study information. Trials were considered nonrandomised if concealment of allocation to treatment groups was classified as "inadequate". The study status was classified as "completed", "discontinued", "ongoing" or "unclear". The publication status of completed or discontinued RCTs was classified as "published" if a full-text paper on final study results (completed trials) or interim results (discontinued trials) was available, and "unpublished" if this was not the case. The type of sponsorship was also noted for all trials.</p> <p>Results</p> <p>A total of 28 RCTs referring to at least 2755 planned or analysed patients met the inclusion criteria: 13 RCTs had been completed, 6 had been discontinued, 6 were ongoing, and the status of 3 RCTs was unclear. Full-text papers were available on 30% of patients in the 19 completed or discontinued RCTs (495 analysed patients in 10 published RCTs vs. 1154 planned patients in 9 unpublished RCTs). Most information about conference abstracts and unpublished study information referring to trials that were unpublished at the time these documents were generated was obtained from the manufacturer Kinetic Concepts Inc. (KCI) (19 RCTs), followed by The Cochrane Library (18) and a systematic review (15). We were able to obtain some information on the methods of unpublished RCTs, but results data were either not available or requests for results data were not answered; the results of unpublished RCTs could therefore not be considered in the review. One manufacturer, KCI, sponsored the majority of RCTs (19/28; 68%). The sponsorship of the remaining trials was unclear.</p> <p>Conclusion</p> <p>Multi-source comprehensive searches identify unpublished RCTs. However, lack of access to unpublished study results data raises doubts about the completeness of the evidence base on NPWT.</p
Disagreement in primary study selection between systematic reviews on negative pressure wound therapy
<p>Abstract</p> <p>Background</p> <p>Primary study selection between systematic reviews is inconsistent, and reviews on the same topic may reach different conclusions. Our main objective was to compare systematic reviews on negative pressure wound therapy (NPWT) regarding their agreement in primary study selection.</p> <p>Methods</p> <p>This retrospective analysis was conducted within the framework of a systematic review (a full review and a subsequent rapid report) on NPWT prepared by the Institute for Quality and Efficiency in Health Care (IQWiG).</p> <p>For the IQWiG review and rapid report, 4 bibliographic databases (MEDLINE, EMBASE, The Cochrane Library, and CINAHL) were searched to identify systematic reviews and primary studies on NPWT versus conventional wound therapy in patients with acute or chronic wounds. All databases were searched from inception to December 2006.</p> <p>For the present analysis, reviews on NPWT were classified as eligible systematic reviews if multiple sources were systematically searched and the search strategy was documented. To ensure comparability between reviews, only reviews published in or after December 2004 and only studies published before June 2004 were considered.</p> <p>Eligible reviews were compared in respect of the methodology applied and the selection of primary studies.</p> <p>Results</p> <p>A total of 5 systematic reviews (including the IQWiG review) and 16 primary studies were analysed. The reviews included between 4 and 13 primary studies published before June 2004. Two reviews considered only randomised controlled trials (RCTs). Three reviews considered both RCTs and non-RCTs. The overall agreement in study selection between reviews was 96% for RCTs (24 of 25 options) and 57% for non-RCTs (12 of 21 options). Due to considerable disagreement in the citation and selection of non-RCTs, we contacted the review authors for clarification (this was not initially planned); all authors or institutions responded. According to published information and the additional information provided, most differences between reviews arose from variations in inclusion criteria or inter-author study classification, as well as from different reporting styles (citation or non-citation) for excluded studies.</p> <p>Conclusion</p> <p>The citation and selection of primary studies differ between systematic reviews on NPWT, particularly with regard to non-RCTs. Uniform methodological and reporting standards need to be applied to ensure comparability between reviews as well as the validity of their conclusions.</p
Reporting bias in medical research - a narrative review
Reporting bias represents a major problem in the assessment of health care interventions. Several prominent cases have been described in the literature, for example, in the reporting of trials of antidepressants, Class I anti-arrhythmic drugs, and selective COX-2 inhibitors. The aim of this narrative review is to gain an overview of reporting bias in the medical literature, focussing on publication bias and selective outcome reporting. We explore whether these types of bias have been shown in areas beyond the well-known cases noted above, in order to gain an impression of how widespread the problem is. For this purpose, we screened relevant articles on reporting bias that had previously been obtained by the German Institute for Quality and Efficiency in Health Care in the context of its health technology assessment reports and other research work, together with the reference lists of these articles
European expert recommendations on clinical investigation and evaluation of high-risk medical devices for children.
Several high-risk medical devices for children have become unavailable in the European Union (EU), since requirements and costs for device certification increased markedly due to the EU Medical Device Regulation. The EU-funded CORE-MD project held a workshop in January 2023 with experts from various child health specialties, representatives of European paediatric associations, a regulatory authority and the European Commission Directorate General Health and Food Safety. A virtual follow-up meeting took place in March 2023. We developed recommendations for investigation of high-risk medical devices for children building on participants' expertise and results of a scoping review of clinical trials on high-risk medical devices in children. Approaches for evaluating and certifying high-risk medical devices for market introduction are proposed