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La verificació aleatòria: una estratègia per millorar i avaluar la qualitat de l'entrada de dades

Se aborda la problemática de la reducción de los errores que se producen durante la introducción de los datos y que no pueden controlarse mediante protecciones automáticas. Frente a este problema, la estrategia habitual es la "doble entrada" (DE) de los datos, la cual aumenta considerablemente el coste de la investigación. Como alternativa a esta estrategia se propone un nuevo procedimiento, implementado en el Sistema DAT, que se basa en un proceso de "verificación aleatoria" (VA) de un porcentaje del total de datos. Además de reducir el coste, la VA ofrece otras ventajas como el hecho de proporcionar una estimación del porcentaje de errores, y ofrecer un índice de aptitud y eficacia de los operadores. En la segunda parte del artículo se presentan los resultados de un experimento que sustenta la hipótesis de que la VA aumenta la eficacia de la entrada de datos, sin mengua de la eficiencia, cuando se compara con situaciones en las cuales no se aplica ningún control que permita obtener un indicador sobre la calidad de los datos que se introducen

Safety culture in the Spanish nuclear power plants through the prism of high reliability organization, resilience and conflicting objectives theories

Safety culture is the result of values, attitudes, and perceptions of the members of an organization that prioritize safety over competing goals. Previous research has shown the impact that organizational aspects can have in safety performance. Under the prism of the theoretical approaches from the high reliability organizations theory (HROT), resilience engineering (RE), and conflicting objectives perspective, this study was aimed at describing the overall main safety culture traits of the Spanish nuclear power plants, as well as identifying particularities associated with subcultures. For this purpose, a statistical analysis of safety culture surveys and behavioral anchored rating scales (BARS), handed over to all the operating Spanish nuclear power plants, was carried out. Results reveal that safety is a recognized value that prevails over production, there is a high degree of standardization, power plants are better prepared to organize plans and strategies than to adapt and cope with the needs of a crisis, and there is a critical and fragmented perception about the processes of resources allocation. Findings also identify that sociodemographic aspects, such as work location and contractual relationship, seem to be shaping differentiated visions. Several safety implications linked to the results are discussed

Differences in picture naming between children with cochlear implants and children with typical hearing

Increase in the auditory abilities of children with cochlear implants (CIs) has led to an improvement in naming tasks, although divergent results are still being reported; this strongly suggests that further studies are needed. The study aims to compare the responses in a picture-naming activity between the complete population of children aged 5 to 7 with cochlear implants in Catalonia -Spain- (N = 31), without developmental problems, and a matched sample of 31 children with typical hearing. A picture-naming task was used to assess their lexical naming abilities. The results show that children with CIs provide more non-responses, they produce fewer words correctly, they require a longer reaction time and they commit more picture-naming errors than children with typical hearing. The auditory age does significantly affect the results, but not the type of implant. In spite of the hearing gain achieved with the cochlear implant and the listening experience progressively achieved in distinct contexts, further explicit work on lexical naming in speech-therapy intervention is clearly required. Picture naming, Cochlear implant, Childhood, Educatio

Revisiones Sistemáticas en Ciencias de la Salud

Translated title of the contribution: Systematic reviews in Health Science

Análisis de datos faltantes mediante redes neuronales artificiales

En los últimos años se ha consolidado el uso de redes neuronales artificiales como complemento a los métodos estadísticos. Sin embargo, no se ha profundizado en el estudio de cómo las redes neuronales artificiales se ven afectadas por la presencia de datos faltantes, ni en el establecimiento de las mejores estrategias para abordarlos durante la fase de análisis estadístico. En nuestro trabajo investigamos la eficacia de diversas técnicas para afrontar los datos faltantes en análisis descriptivos univariantes y en la generación de modelos de clasificación, entre las que se incluyen redes neuronales del tipo perceptrón multicapa y de función base radial. Nuestros resultados sugieren que, en general, para los tipos de variables estudiados las redes neuronales artificiales son más eficaces en la disminución del error de imputación que otras técnicas de análisis ampliamente utilizadas cuando existe un nivel de correlación no nulo con otras variables registradasIn the last years it has been consolidated the use of artificial neural nets as a complement to statistical methods. However, it has not been deeply studied neither how the presence of missing data affects artificial neuronal nets nor the establishment of the best strategies to treat missing data in the stage of statistical analysis. In our work we investigate the effectiveness of different techniques to face missing data in univariant descriptive analysis and in the generation of classification models, including multilayer perceptron and radial basis function neural nets. Our results suggest that, in general, artificial neural nets are more effective in decreasing the imputation error than other broadly used analysis technique

Tools to assess the measurement properties of quality of life instruments : a meta-review

Objective: This meta-review aims to discuss the methodological, research and practical applications of tools that assess the measurement properties of instruments evaluating Health-Related Quality of Life (HRQoL) that have been reported in systematic reviews. Design: Meta-review. Methods: Electronic search from January 2008 to May 2020 was carried out on PubMed, CINAHL, PsycINFO, SCOPUS, WoS, Consensus-based Standards for the selection of health Measurement Instruments (COSMIN) database, Google Scholar, and ProQuest Dissertations & Theses. Results: A total of 246 systematic reviews were assessed. Concerning the quality of the review process, some methodological shortcomings were found, such as poor compliance with reporting or methodological guidelines. Regarding the procedures to assess the quality of measurement properties, 164 (66.6 %) of reviewers applied one tool at least. Tool format and structure differed across standards or scientific traditions (i.e. psychology, medicine and economics), but most assess both measurement properties and the usability of instruments. As far as the results and conclusions of systematic reviews are concerned, only 68 (27.5 %) linked the intended use of the instrument to specific measurement properties (e.g. evaluative use to responsiveness). Conclusions: The reporting and methodological quality of reviews have increased over time, but there is still room for improvement regarding adherence to guidelines. The COSMIN would be the most widespread and comprehensive tool to assess both the risk of bias of primary studies, and the measurement properties of HRQoL instruments for evaluative purposes. Our analysis of other assessment tools and measurement standards can serve as a starting point for future lines of work on the COSMIN tool, such as considering a more comprehensive evaluation of feasibility, including burden and fairness; expanding its scope for measurement instruments with a different use than evaluative; and improving its assessment of the risk of bias of primary studie

Development and validation of the Adolescent Sexting Scale (A-SextS) with a Spanish sample

'Sexting' is generally defined as the exchange of sexual media content via the internet. However, research on this topic has underscored the need to seek greater consensus when considering different conceptual elements that make up this definition. The aim of this study was to develop and validate an instrument for measuring sexting among adolescents, in order to cover a gap identified in the previous literature. The Adolescent Sexting Scale (A-SextS for short) was developed for validation on a sample of 579 Spanish secondary school pupils between the ages of 11 and 18. Evidence for face, content, concurrent, and criterion validity were assessed. A comprehensive set of 64 items, covering six defining characteristics of sexting (e.g., actions, recipient, media format, degree of sexual explicitness), was constructed after conducting an extensive literature review, two discussion groups, and a pilot study. Sexting prevalence rates measured by A-SextS were mostly concurrent with those found in previous studies. A-SextS subscales produced statistically significant positive associations with pornography consumption and physical sexual intercourse. The study shows that A-SextS can be an integrating instrument that facilitates a rigorous and comprehensive assessment of adolescent sexting experiences, as well as the formulation of an operationalized definition of the practice of sextin

Suitability of three different tools for the assessment of methodological quality in ex post facto studies

There is no clear candidate tool for assessing the methodological quality of ex post facto studies in systematic reviews and meta-analyses yet. Our purpose is to thoroughly analyze the psychometric properties of the three most comprehensive assessment tools of this kind published up to 2010. We selected these tools from a previous systematic review, and we applied each one to assess the quality of 10 prospective studies, 10 retrospective studies with quasi-control group, and 10 cross-sectional studies. Inter-rater reliability for the first two aforementioned research designs is moderate only for one of the selected tools, and moderate to high for all of them for cross-sectional studies. Agreement between tools is low in general, although the inferred aspects show that the tools have a relative good conceptual overlapping in most of the domains. According to these results we recommend two tools for assessing cross-sectional studies, but we consider that the tools applicable to prospective studies or retrospective studies with quasi-control group require further testing. The 30 concrete aspects that we have inferred from the items of the three analyzed tools can be used as starting point to develop a new tool of this kin