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Background To assess the quality of reporting of RCT protocols approved by UK research ethics committees before and after the publication of the Standard Protocol Items: Recommendations for Interventional Trials (SPIRIT) guideline. Methods We had access to RCT study protocols that received ethical approval in the UK in 2012 (n=103) and 2016 (n=108). From those, we assessed the adherence to the 33 SPIRIT items (i.e. a total of 64 components of the 33 SPIRIT items). We descriptively analysed the adherence to SPIRIT guidelines as proportion of adequately reported items (median and interquartile range [IQR]) and stratified the results by year of approval and sponsor. Results The proportion of reported SPIRIT items increased from a median of 64.9% (IQR, 57.6–69.2%) in 2012 to a median of 72.5% (IQR, 65.3–78.3%) in 2016. Industry-sponsored RCTs reported more SPIRIT items in 2012 (median 67.4%; IQR, 64.1–69.4%) compared to non-industry-sponsored trials (median 59.8%; IQR, 46.5–67.7%). This gap between industry- and non-industry-sponsored trials increased in 2016 (industry-sponsored: median 75.6%; IQR, 71.2–79.0% vs non-industry-sponsored: median 65.3%; IQR, 51.6–76.3%). Conclusions The adherence to SPIRIT guidelines has improved in the UK from 2012 to 2016 but remains on a modest level, especially for non-industry-sponsored RCTs.

IMPORTANCE: Clinical trial registries are important for gaining an overview of ongoing research efforts and for deterring and identifying publication bias and selective outcome reporting. The reliability of the information in trial registries is uncertain. OBJECTIVE: To assess the reliability of information across registries for trials with multiple registrations. EVIDENCE REVIEW: For this systematic review, 360 protocols of randomized clinical trials (RCTs) approved by research ethics committees in Switzerland, the UK, Canada, and Germany in 2012 were evaluated. Clinical trial registries were searched from March to September 2019 for corresponding registrations of these RCTs. For RCTS that were recorded in more than 1 clinical trial registry, key trial characteristics that should be identical among all trial registries (ie, sponsor, funding source, primary outcome, target sample size, trial status, date of first patient enrollment, results available, and main publication indexed) were extracted in duplicate. Agreement between the different trial registries for these key characteristics was analyzed descriptively. Data analyses were conducted from May 1 to November 30, 2020. Representatives from clinical trial registries were interviewed to discuss the study findings between February 1 and March 31, 2021. FINDINGS: The analysis included 197 RCTs registered in more than 1 trial registry (151 in 2 registries and 46 in 3 registries), with 188 trials in ClinicalTrials.gov, 185 in the European Union Drug Regulating Authorities Clinical Trials Database (EudraCT), 20 in ISRCTN, and 47 in other registries. The agreement of key information across all registries was as follows: 178 of 197 RCTs (90%; 95% CI, 85%-94%) for sponsor, 18 of 20 (90%; 95% CI, 68%-99%) for funding source (funding was not reported on ClinicalTrials.gov), 154 of 197 (78%; 95% CI, 72%-84%) for primary outcome, 90 of 197 (46%; 95% CI, 39%-53%) for trial status, 122 of 194 (63%; 95% CI, 56%-70%) for target sample size, and 43 of 57 (75%; 95% CI, 62%-86%) for the date of first patient enrollment when the comparison time was increased to 30 days (date of first patient enrollment was not reported on EudraCT). For results availability in trial registries, agreement was 122 of 197 RCTs (62%; 95% CI, 55%-69%) for summary data reported in the registry and 91 of 197 (46%; 95% CI, 39%-53%) for whether a published article with the main results was indexed. Different legal requirements were stated as the main reason for inconsistencies by representatives of clinical trial registries. CONCLUSIONS AND RELEVANCE: In this systematic review, for a substantial proportion of registered RCTs, information about key trial characteristics was inconsistent across trial registries, raising concerns about the reliability of the information provided in these registries. Further harmonization across clinical trial registries may be necessary to increase their usefulness.

Background/research question: Clinical trial registries are supposed to give a comprehensive overview of all ongoing randomised clinical trials (RCTs) which helps to avoid duplication of research and to estimate and control publication bias as well as selective reporting. As it remains unclear [for full text, please go to the a.m. URL], Nützliche patientenrelevante Forschung; 21. Jahrestagung des Deutschen Netzwerks Evidenzbasierte Medizin

На підставі аналізу способів визначення термічного поперечного перерізу захоплення дефектом носіїв заряду зі спектрів DLTS розкриті можливі причини суттєвих похибок при визначенні даного параметра. Окреслено межі застосовності кожного зі способів за рядом критеріїв — характеристики досліджуваної напівпровідникової структури, термічна залежність поперечного перерізу захоплення, тощо. Сформульовано вимоги до апаратної частини та запропоновано схему DLTS спектрометра, здатного реалізувати один з прямих способів визначення поперечного перерізу захоплення носіїв., На основании анализа способов определения термического поперечного сечения захвата дефектом носителей заряда со спектров DLTS раскрыты возможные причины существенных погрешностей при определении данного параметра. Очерчены границы применимости каждого из способов по ряду критериев характеристики исследуемой полупроводниковой структуры, термическая зависимость поперечного сечения захвата, и т.п. Сформулированы требования к аппаратной части и предложена схема DLTS спектрометра, способного реализовать один из прямых способов определения поперечного сечения захвата носителей., On the basis of the analysis of determination ways of thermal charge carriers capture cross section by defect from DLTS spectra the possible causes of essential measurement errors of the given parameter are revealed. The applicability borders of each way on a number of criteria — the characteristics of the investigated semiconductor structures, thermal dependence of the capture cross section, etc. are outlined. Requirements to the hardware are formulated and the schematic of the DLTS spectrometer, capable to realise one of direct ways of carriers capture cross section determination is proposed.

We compare two approaches to the atomic, electronic, and magnetic structures of LaMnO3 bulk and the (001), (110) surfaces—hybrid B3PW with optimized LCAO basis set (CRYSTAL-2003 code) and GGA-PW91 with plane-wave basis set (VASP 4.6 code). Combining our calculations with those available in the literature, we demonstrate that combination of nonlocal exchange and correlation used in hybrid functionals allows to reproduce the experimental magnetic coupling constants Jab and Jc as well as the optical gap. Surface calculations performed by both methods using slab models show that the antiferromagnetic (AF) and ferromagnetic (FM) (001) surfaces have lower surface energies than the FM (110) surface. Both the (001) and (110) surfaces reveal considerable atomic relaxations, up to the fourth plane from the surface, which reduce the surface energy by about a factor of 2, being typically one order of magnitude larger than the energy difference between different magnetic structures. The calculated (Mulliken and Bader) effective atomic charges and the electron density maps indicate a considerable reduction of the Mn and O atom ionicity on the surface.