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ABSTRACT OBJECTIVE This study aims to propose a comprehensive alternative to the Bland-Altman plot method, addressing its limitations and providing a statistical framework for evaluating the equivalences of measurement techniques. This involves introducing an innovative three-step approach for assessing accuracy, precision, and agreement between techniques, which enhances objectivity in equivalence assessment. Additionally, the development of an R package that is easy to use enables researchers to efficiently analyze and interpret technique equivalences. METHODS Inferential statistics support for equivalence between measurement techniques was proposed in three nested tests. These were based on structural regressions with the goal to assess the equivalence of structural means (accuracy), the equivalence of structural variances (precision), and concordance with the structural bisector line (agreement in measurements obtained from the same subject), using analytical methods and robust approach by bootstrapping. To promote better understanding, graphical outputs following Bland and Altman’s principles were also implemented. RESULTS The performance of this method was shown and confronted by five data sets from previously published articles that used Bland and Altman’s method. One case demonstrated strict equivalence, three cases showed partial equivalence, and one showed poor equivalence. The developed R package containing open codes and data are available for free and with installation instructions at Harvard Dataverse at https://doi.org/10.7910/DVN/AGJPZH. CONCLUSION Although easy to communicate, the widely cited and applied Bland and Altman plot method is often misinterpreted, since it lacks suitable inferential statistical support. Common alternatives, such as Pearson’s correlation or ordinal least-square linear regression, also fail to locate the weakness of each measurement technique. It may be possible to test whether two techniques have full equivalence by preserving graphical communication, in accordance with Bland and Altman’s principles, but also adding robust and suitable inferential statistics. Decomposing equivalence into three features (accuracy, precision, and agreement) helps to locate the sources of the problem when fixing a new technique.

The industrial sector of Cuenca represents an icon of development and progress of this city. The problem of studying this sector is that it calculates traditional financial ratios exposed to volatile contexts with high uncertainty. The aim of this research is to estimate financial ratios with fuzzy logic approach in industrial companies of Cuenca city, Ecuador, due to the great importance of estimating these ratios to determine the financial health of these organizations. The research is descriptive, with a quantitative approach, using the development of expert and counter-expertise techniques, applying a form of calculation through Triangular Fuzzy Numbers (TFNs), and confidence intervals, instruments of fuzzy logic. The results obtained at 80% and 90% of the degree of presumption, are equivalent to the bands [1,488, 1,506] and [1,494, 1,503] respectively, corresponding to the liquid ratio; in a similar way the other working capital ratios are presented in the study. This new estimate will allow directors and managers to make more accurate decisions for the benefit of their companies, overcoming traditional barriers to be framed in the objectivity and reality of the current market.

The original idea of rejecting studies with low power and authorising them if their power is sufficiently high is reasonable and even an obligation, although in practice this reasoning is heavily constrained by the fact that the power of a study depends on several factors, rather than a single one. Furthermore, there is no threshold separating 'high' power values from 'low' power values'. However, if the result is very significant, considering how powerful it was it makes little sense after the study has been carried out. It is only possible to take advantage of the result. Situations in which this result is not statistically significant warrant further consideration. Consideration of the power may be useful in these circumstances. This article focuses on the position that should be adopted in these cases, and it shows that in order to draw reasonable conclusions about the effect size of the population, calculating the confidence interval is more useful than calculating the power, and its interpretation is more easily understood by physicians who lack training in statistical analysis.

ABSTRACT The goal of this study was to use the spatial bootstrap method to model the spatial dependence structure of soybean yield and soil chemical attributes in an agricultural area. The study involved developing confidence intervals in probability plots to determine the probability distributions assumed by the data; determine the empirical distributions of the semivariances and model parameters, allowing to obtain statistics and confidence intervals; and to construct maps for the variables. The quantile-quantile plots indicated that the data follows a normal distribution. The confidence intervals for the semivariances helped to model the spatial dependence structure, and the descriptive statistics of the bootstrap replicates of the model parameters allowed to test the consistency of the estimates. The soil chemical attributes (calcium, potassium, and organic matter) were at levels suitable for soybean cultivation. However, the pH was below the ideal range in most of the study area, and water stress during cultivation decreased the mean yield. Therefore, according to the results, a recommendation to the farmer is to correct the soil pH to increase the yield.

Introduction: This article explores the use of learning curves and confidence intervals in a time study carry out in a scale assembly line during a laboratory practice at the University of La Salle. Objective: The objective of this research is to show the use of confidence intervals and learning curves for the identification of stable processes and subsequent standardization of timing Methodology: The methodology used consists in two phases: Analysis for the study of times and establishment of standard times; the first consist in the calculation of the number of cycles, depuration of atypical data and the use of the curves to determine the processes suitable for the standardization, and the second phase is the calculation of the standard times. Results: The analysis allowed to determine that is only possible to standardize two of the five processes of the system under study because of the variability of them. Conclusions: Given the research, is possible to conclude that a process should be standardized only if it presents a stable behavior respect to the normal rhythm of work, which is showed in the learning curve; otherwise, the process will obtain partial standard times.

Recent population trends of the houbara bustard in the Canary Islands. Methods and conservation statusDetermining conservation status requires rigorous and reliable data about population sizes and trends, especially if they have to be applied to islands where the species have small populations. The Canary bustard houbara (Chlamydotis undulata fuertaventurae) is catalogued as ‘in danger’ by the Red Book of the Birds of Spain. This work analyzes the value of previously published information on the species using the method of adjacent linear transects separated by 200 m, as a baseline for establishing robust population trends in 30 important areas (ranging from 1.3 to 12.8 km2) for the houbara in the islands of Lanzarote and Fuerteventura (Canary Islands). Censuses were repeated on the same dates (from November to December) and localities as those carried out in 1994, 2004 and 2006. The detection probability of the houbara was estimated by means of distance sampling, being 0.42 up to 250 m from the observer, and 0.82 in the main census belt of 100 m on either side of the line transect. The method of adjacent linear transects —counting the maximum number of hubaras detected— provides accurate figures of population densities (detection of 95.2% of the birds). The previous estimations of houbara densities can therefore be considered highly trustworthy, with a probable average underestimation of only 5 %. Nevertheless, the confidence intervals of density estimations using only one census were very large. Therefore, with only one census per sampling area and year it is not possible to obtain precise estimates of houbara densities with small variation around the average value. This raises concern when trying to obtain solid evidence about the increases–decreases of houbara populations comparing different dates or study areas. The density of the Canary Island hubara bustard decreased significantly from 2004/2006 to 2011 in eight areas of Fuerteventura (Vega Vieja, Los Alares–Pocetas, Matas Blancas, Lorenzo– Diviso, Corralejo, Lajares and Fimapaire) and in two areas of Lanzarote (Argana and La Santa). Conversely, the density of the houbara significantly increased in three areas of Lanzarote (Zonzamas, Guatiza and Llano de las Maretas). As a whole, average population density did not differ significantly between 2004/2006 and 2011 in Fuerteventura (slight decrease of 29% in 2011), but there was a significant increase in Lanzarote (increase of 60% from 2004/2006 to 2011). The change in density from 2004/2006 to 2011 tended to be an increase in areas further from paved roads, and a decrease in locations predominantly covered by loose sandy soils.

Vazões máximas são grandezas hidrológicas aplicadas a projetos de obras hidráulicas e vazões mínimas são utilizadas para a avaliação das disponibilidades hídricas em bacias hidrográficas e comportamento do escoamento subterrâneo. Neste estudo, objetivou-se à construção de intervalos de confiança estatísticos para vazões máximas e mínimas diárias anuais e sua relação com as características fisiográficas das 6 maiores bacias hidrográficas da região Alto Rio Grande à montante da represa da UHE-Camargos/CEMIG. As distribuições de probabilidades Gumbel e Gama foram aplicadas, respectivamente, para séries históricas de vazões máximas e mínimas, utilizando os estimadores de Máxima Verossimilhança. Os intervalos de confiança constituem-se em uma importante ferramenta para o melhor entendimento e estimativa das vazões, sendo influenciado pelas características geológicas das bacias. Com base nos mesmos, verificou-se que a região Alto Rio Grande possui duas áreas distintas: a primeira, abrangendo as bacias Aiuruoca, Carvalhos e Bom Jardim, que apresentaram as maiores vazões máximas e mínimas, significando potencialidade para cheias mais significativas e maiores disponibilidades hídricas; a segunda, associada às bacias F. Laranjeiras, Madre de Deus e Andrelândia, que apresentaram as menores disponibilidades hídricas.Maximum discharges are applied to hydraulic structure design and minimum discharges are used to characterize water availability in hydrographic basins and subterranean flow. This study is aimed at estimating the confidence statistical intervals for maximum and minimum annual discharges and their relationship wih the physical characteristics of basins in the Alto Rio Grande Region, State of Minas Gerais. The study was developed for the six (6) greatest Alto Rio Grande Region basins at upstream of the UHE-Camargos/CEMIG reservoir. Gumbel and Gama probability distribution models were applied to the maximum and minimum long-term discharges respectively, using Maximum Likelihood estimators. Confidence intervals are important tools for better understand and estimation of water flows, being influenced by the geological characteristics of the basins. Based on the results, we could distinguish two hydrological systems: Aiuruoca, Carvalhos, and Bom Jardim basins, which have produced the greatest maximum and minimum discharges, which means they are more prone to floods, and have more water availability; and F. Laranjeiras, Madre de Deus and Andrelandia basins, which presented smaller water availability.

En el presente trabajo, los autores revisan algunos conceptos básicos sobre variables y procesamiento estadístico para obtener el valor "p" como el Test t de Student y el método de Chi-Cuadrado, así como la forma de calcular Intervalos de Confianza con las herramientas estadísticas del programa informático Excel (Microsoft), con ejemplos y un ejercicio para el lector.Authors of this paper review some basic concepts about variables and statistical processing to obtain "p" value, such as Student t-Test and Chi-Square test, as well as a way of obtaining Confidence Intervals with statistical tools from Excel software (Microsoft), providing examples and an exercise to the reader.

Infant size at birth is a useful indicator to evaluate fetal growth in relation to gestational age. There is no standard model to create anthropometric reference curves in neonates, but the method chosen could determine the reference values estimated. We describe the methods used to construct population-based reference curves of birth weight for gestational age in Catalonia, Spain. These methods included detection of implausible values of birth weight for gestational age by a probabilistic cluster model, utilization of the Generalized Additive Model for Location and Scale method to obtain smoothed percentiles and z-scores, and calculation of 95% confidence intervals by bootstrapping. To our knowledge, these are the first reference curves in neonates constructed through a method allowing asymmetric distributions with kurtosis to be modelled. Estimation of confidence intervals is useful to determine which reference intervals can be employed to assess newborn size.La evaluación del tamaño en el nacimiento es uni ndicador útil para evaluar elcrecimiento fetal en relación con la edad gestacional. No hay un modelo estándar para crear curvas de referencia antropométricas en recién nacidos, pero el método escogido podría determinar los valores de referencia estimados. Describimos los métodos utilizados para elaborar las curvas de referencia poblacionales del peso al nacer según la edad gestacional en Cataluña, España. Estos métodos incluyen la detección de los valores inverosímiles de peso al nacer para la edad gestacional mediante un modelo probabilístico de agrupaciones, la utilización del modelo Generalized Additive Model for Location and Scale para la obtención de los percentiles alisados, y las puntuaciones z y el cálculo de los intervalos de confianza del 95% mediante remuestreos. Hasta donde conocemos, éstas son las primeras curvas de referencia en recién nacidos en las cuales se ha utilizado un método que permite modelar distribuciones asimétricas con curtosis. La valoración de intervalos de confianza es útil para determinar los intervalos de referencia que pueden emplearse para evaluar el tamañoo del recién nacido.

Objetivou-se, neste trabalho, avaliar intervalos de confiança de diferentes funções lineares compostas por proporções binomiais construídas com base no método de Wald e Wald ajustado utilizando a técnica de bootstrap infinito. Considerados diversos tamanhos amostrais (n is), parâmetros (p) e número de coeficientes das funções lineares. Concluiu-se, por meio das probabilidades de cobertura dos intervalos de confiança das populações binomiais, cujas proporções foram baixas (p=0,2) e considerando diferentes tamanhos de amostras, que a generalização bootstrap do método de Wald ajustado foi eficiente para funções lineares cujos coeficientes indicaram a comparação de uma proporção versus as demais.This work aimed to evaluate confidence intervals of different linear functions of binomial proportions base on Wald and Wald's adjusted method using the infinity bootstrap technique. Several sample sizes (n i), binomial parameters (p) and number of coefficients of the linear functions were considered. One concluded through the probabilities of binomial population confidence covered intervals that the bootstrap generalization of adjusted Wald's method was efficient for linear functions whose coefficients indicated a comparison of versus the others proportion (p=0.2) considering different sample sizes.

INTRODUCCIÓN El desarrollo de proyectos de investigación suele demandar del uso de herramientas matemáticas para expresar en términos numéricos o gráficos diversas magnitudes, tales como frecuencias, diferencias, o asociaciones. OBJETIVOS El presente estudio se propone describir la utilización que se hace de las herramientas estadísticas básicas, haciendo especial énfasis en el uso de las pruebas de significación estadística y los intervalos de confianza, para la presentación de resultados de investigación en los artículos publicados en una reconocida revista de la salud pública en Colombia. MÉTODOS Se realizó una revisión de los 84 artículos originales publicados en dicha revista entre 2013 y 2014. RESULTADOS El recurso más empleado es la utilización de análisis de frecuencias (89,3%), seguido de los valores p (65,5%) y los intervalos de confianza (53,6%); el 48,9% de los artículos utiliza a la vez intervalos de confianza y valores p para la presentación de resultados y el 29,8% ninguno de los dos. El 16,7% de los artículos sólo utiliza valores p y el 4,8% sólo intervalos de confianza. CONCLUSIONES La estadística descriptiva es una herramienta que se utiliza con asiduidad en la presentación de resultados y que las críticas y advertencias sugiriendo que se evite el uso exclusivo de las pruebas de significación estadística en la presentación de resultados no son cabalmente tenidas en cuenta en el análisis y presentación de los resultados de investigación.

El coeficiente alfa de Cronbach es el modo más habitual de estimar la fiabilidad de pruebas basadas en Teoría Clásica de los Test. En dicha estimación, los investigadores usualmente omiten informar intervalos de confianza para el coeficiente, un aspecto no solo recomendado por los especialistas, sino también requerido explícitamente en las normas editoriales de algunas revistas especializadas. Esta situación puede atribuirse a que los métodos de estimación de intervalos de confianza son poco conocidos, además de no estar disponibles al usuario en los programas estadísticos más populares. Así, en este trabajo se presenta un programa desarrollado dentro del sistema estadístico ViSta que permite calcular intervalos de confianza basados en el enfoque clásico y mediante la técnica bootstrap. Se espera promover la inclusión de intervalos de confianza para medidas de fiabilidad, facilitando el acceso a las herramientas necesarias para su aplicación. El programa es gratuito y puede obtenerse enviando un mail de solicitud al autor del trabajo.Cronbach's alpha coefficient is the most popular way of estimating reliability in measurement scales based on Classic Test Theory. When estimating it, researchers usually omit to report confidence intervals of this coefficient, as it is not only recommended by experts, but also required by some journal's guidelines. This situation is because the different methods of estimating confidence intervals are not well-known by researchers, as well as they are not being available among the most popular statistical packages. Therefore, this paper describes a computer program integrated into the ViSta statistical system, which allows computing confidence intervals based on the classical approach and using bootstrap technique. It is hoped that this work promotes the inclusion of confidence intervals of reliability measures, by increasing the availability of the required computer tools. The program is free and it can be obtained by sending an e-mail to the author.

OBJETIVO: Apresentar uma aplicação da regressão logística para estimar razões de prevalência ou risco relativo, e o uso do método delta para a estimativa de intervalos de confiança. MÉTODOS: Utilizou-se o método delta, visto que esta técnica é adequada para estimar variâncias de funções não lineares de variáveis aleatórias, do tipo razão de proporções. O método baseia-se na expansão da função em série de Taylor, provendo uma aproximação para o cálculo das variâncias. Para estimar as razões de proporções e as respectivas variâncias, que permitem a estimação dos intervalos de confiança, desenvolveu-se programa utilizando-se o módulo matricial do SAS. A aplicação prática do modelo proposto é feita utilizando-se dados de um estudo transversal com uma amostra de 611 mulheres, para testar a hipótese de que a falta de compartilhamento do trabalho doméstico associa-se com altos escores de sintomas psicológicos medidos através de um questionário validado. As razões de prevalência calculadas através da regressão logística, e os intervalos de confiança estimados pelo método delta foram comparadas com os resultados obtidos pela técnica de Mantel-Haenszel. RESULTADOS: As estimativas pontuais das razões de prevalência brutas, cruas ou ajustadas, obtidas através da regressão logística, foram semelhantes às encontradas na análise tabular. Também os limites dos intervalos de confianças para as razões de prevalência através do método delta foram praticamente iguais em relação aos encontrados através da técnica de Mantel-Haenszel. CONCLUSÕES: Os resultados apóiam o uso do método delta para estimar intervalos de confiança para razões de proporção. Esse método deve ser visto como uma alternativa para situações em que o efeito em estudo (variável dependente) não é raro, situação onde a "odds ratio" se afasta das medidas epidemiológicas caracterizadas como razão de proporções.OBJECTIVE: To present an application of logistic regression modelling to estimate ratios of proportions, such as prevalence ratio or relative risk, and the Delta Method to estimate confidence intervals. METHOD: The Delta Method was used because it is appropriate for the estimation of variance of non-linear functions of random variables. The method is based on Taylor's series expansion and provides a good approximation of variance estimates. A computer program, utilizing the matrix module of SAS, was developed to compute the variance estimates. A practical demonstration is presented with data from a cross-sectional study carried out on a sample of 611 women, to test the hypothesis that the lack of housework sharing is associated with high scores of psychological symptoms as measured by a validated questionnaire. RESULTS: Crude and adjusted prevalence ratio estimated by logistic regression were similar to those estimated by tabular analysis. Also, ranges of the confidence intervals of the prevalence ratio according to the Delta Method were nearly equal to those obtained by the Mantel-Haenszel approach. CONCLUSIONS: The results give support to the use of the Delta Method for the estimation of confidence intervals for ratios of proportions. The method should be seen as an alternative for situations in which the need to control a large number of potential confounders limits the use of stratified analysis.

Boxplots are a useful and widely used graphical technique to explore data in order to better understand the information we are working with. Boxplots display the first, second and third quartile as well as the interquartile range and outliers of a data set. The information displayed by the boxplot, and most of its variations, is based on the data’s median. However, much of scientific applications analyse and report data using the mean. In this paper, we propose a variation of the classical boxplot that displays information around the mean. Some information about the median is displayed as well.

Confidence intervals and measures of effect size are gradually becoming the standard way of reporting the results of statistical analyses in research articles, used instead of or in addition to p values. However, this shift in research practices barely affected teaching practices up to now. This paper is the third of a series written to serve as a general reference on the use of confidence intervals in quantitative social sciences. Its purpose is to provide guidelines, advices and useful tricks of the trade that will allow readers (a) to face most of the statistical problems emerging in real-life research settings and (b) to improve their understanding of confidence intervals and answer more efficiently their questions of interest. The first part of the article briefly introduces the basic elements of an approach based on confidence intervals: Calculations, interpretation, and hypothesis testing. The second part is an attempt to present some of the most important (but sometimes neglected) advanced issues concerning confidence intervals: Graphic representations, complex distributions, national surveys, the larger family of interval statistics (e.g., prediction intervals), and the Bayesian approach to probabilities.

Purpose: The aim of this study was to perform a systematic review and meta-analysis to assess the safety and efficacy of interventional treatment for Budd-Chiari syndrome (BCS) complicated by Inferior Vena Cava thrombosis (IVCT) patients., Methods: We evaluated the published studies on interventional treatment for BCS complicated by IVCT. Meta-analysis was used to calculate the combined effect size and their 95% confidence intervals (CI) based on random effect. The publication bias was assessed by Begg's test., Results: Sixteen studies on interventional treatment for BCS complicated by IVCT patient were selected for meta-analysis, a total of 767 BCS complicated by IVCT patients were included. The combined effect size (95% CI) were 99% (98-100%) for the total successful rate of IVC recanalization, 15% (11-21%) for the rate of IVC restenosis after initial operation, 92.0% (86-97%) for the rate of clinical improvement, 76% (68-84%) for the rate of thrombus clearance and 0.00% (0-1%) for the incidence of pulmonary embolism (PE). Through subgroup meta-analysis about the rate of thrombus clearance, we got the pooled results (95% CI) of individualized treatment strategy (ITS) group and non-individualized treatment strategy (non-ITS) group, were 81% (71-92%) and 73% (63-83%), respectively., Conclusions: The interventional treatment for BCS complicated by IVCT patients is safe and effective with low incidence of PE, high thrombus clearance rate, high technically successful rate, good patency, and high clinical improvement rate. Moreover, subgroup analysis indicated that management based on the type and extent of the thrombus is proposed., (Copyright © 2020. Publicado por Elsevier España, S.L.U.)

Introduction and Objectives: Cardiac troponin, a marker of myocardial injury, is frequently observed in patients with COVID-19 infection. Our objective was to analyze myocardial injury and its prognostic implications in patients with and without COVID-19 infection treated in the same period of time., Methods: The present study included patients treated in a university hospital with cardiac troponin I measurements and with suspected COVID-19 infection, confirmed or ruled out by polymerase chain reaction analysis. The impact was analyzed of cardiac troponin I positivity on 30-day mortality., Results: In total, 433 patients were distributed among the following groups: confirmed COVID-19 (n=186), 22% with myocardial injury (n=41); and ruled out COVID-19 (n=247), 21.5% with myocardial injury (n=52). The confirmed and ruled out COVID-19 groups had a similar age, sex, and cardiovascular history. Mortality was significantly higher in the confirmed COVID-19 group than in the ruled out group (19.9% vs 5.3%, P <.001). In Cox multivariate regression analysis, cardiac troponin I was a predictor of mortality in both groups (confirmed COVID-19 group: HR, 3.54; 95%CI, 1.70-7.34; P=.001; ruled out COVID-19 group: HR, 5.57; 95%CI, 1.70-18.20; P=.004). The predictive model analyzed by ROC curves was similar in the 2 groups (P=.701), with AUCs of 0.808 in the confirmed COVID-19 group (0.750-0.865) and 0.812 in the ruled out COVID-19 group (0.760-0.864)., Conclusions: Myocardial injury is detected in 1 in every 5 patients with confirmed or ruled out COVID-19 and predicts 30-day mortality to a similar extent in both circumstances., (Copyright © 2020 Sociedad Española de Cardiología. Published by Elsevier España, S.L.U. All rights reserved.)

Objective: To describe and compare the demographic characteristics and comorbidities of patients with COVID-19 who died in Spanish hospitals during the 2020 pandemic based on whether they were or were not admitted to an intensive care unit (ICU) prior to death., Methods: We performed a secondary analysis of COVID-19 patients who died during hospitalization included by 62 Spanish emergency departments in the SIESTA cohort. We collected the demographic characteristics and comorbidities, determined both individually and estimated globally by the Charlson index (ChI). Independent factors related to ICU admission were identified and different analyses of sensitivity were performed to contrast the consistency of the findings of the principal analysis., Results: We included the 338 patients from the SIESTA cohort that died during hospitalization. Of these, 77 (22.8%) were admitted to an ICU before dying. After multivariate adjustment, 3 out of the 20 basal characteristics analyzed in the present study were independently associated with ICU admission: dementia (no patients with dementia who died were admitted to the ICU: OR = 0, 95%CI = not calculable), active cancer (OR = 0.07; 95%CI = 0.02-0.21) and age (< 70 years: OR = 1, reference; 70-74 years: OR = 0.21; 95%CI = 0.08-0.54; 75-79 years: OR = 0.21; 95%CI = 0.08-0.54; ≥ 80 years: OR = 0.02; 95%CI = 0.01-0.05). The probability of ICU admission significantly increased in parallel to the ChI, even after adjustment for age (ChI 0 points: OR = 0, reference; ChI 1 point: OR = 0.36; 95%CI = 0.16-0.83; ChI 2 points: OR = 0.36; 95%CI = 0.16-0.83; ChI >2 points: OR = 0.09; 95%CI = 0.04-0.23). The sensitivity analyses showed no gross differences compared to the principal analysis., Conclusions: The profile of COVID-19 patients who died without ICU admission is similar to that observed in the usual medical practice before the pandemic. The basal characteristics limiting their admission were age and global burden due to comorbidity, especially dementia and active cancer., (Copyright © 2020 Elsevier España, S.L.U. y SEMICYUC. All rights reserved.)

Introduction: Functional limitations associated with the aging process can lead to the development of depressive symptoms and increase the vulnerability of older adults. Objective: To estimate the association between physical disability and the incidence of clinically significant depressive symptoms in older Mexican adults. Materials and methods: We conducted a retrospective cohort study with data from the Encuesta Nacional sobre Salud y Envejecimiento en México (ENASEM). The analytical sample (n=6,780) included adults over 50 years old with measurements for the main variables and no clinically significant depressive symptoms reported in the first round. These symptoms were evaluated with the CESD-9 scale and disability by means of the report of activities of daily living (ADL) or instrumental activities of daily living (IADL). Descriptive, bivariate, and multivariate analyses were performed using logistic regression models adjusted by sociodemographic variables, health conditions, childhood adversities, social participation, and stressful life events. Results: The incidence of clinically significant depressive symptoms was 25.75% (95% CI: 24,70 - 26,80). Compared to those without IADL limitations, an increased risk of 68% for the development of clinically significant depressive symptoms was found (95% CI: 1.10-2.57; p= 0,015). With the ADL model, the OR for the development of clinically significant depressive symptoms was 1.36 (1.01 -1.81; p= 0.039). Both models were adjusted by confounding variables. Conclusion: Presenting limitations in daily life is an important risk factor for the development of clinically significant depressive symptoms at two years of follow-up.

Background: Tenofovir disoproxil fumarate (TDF) is recommended for the prevention of perinatal transmission of the hepatitis B virus (HBV). This study aimed to systematically assess the efficacy and safety of TDF in pregnant women with chronic HBV and their infants., Material and Methods: Database searches were performed to identify studies blocking the mother-to-child transmission of the hepatitis B virus with tenofovir. The search included pregnant women with chronic HBV infection administered with TDF compared to the no treatment controls, and data from individual studies were pooled using RevMan v5.3 for meta-analysis., Results: Seven studies with a total of 911 patients met the inclusion criteria: 433 patients in the TDF group and 478 patients in the non-TDF group. The HBV mother-to-child transmission rate in the tenofovir group was effectively reduced compared to the control group (RR: 0.18, 95% CI: 0.08-0.40). HBV-DNA positivity was also significantly low in infants from TDF group (RR: 0.17, 95% CI: 0.10-0.30) and the TDF treatment resulted in significantly higher anti-HBs production (RR: 1.11, 95% CI: 1.04-1.18). Similarly, maternal HBV-DNA was suppression was significantly high in the TDF group (RR: 34.16, 95% CI: 16.40-71.13). Women treated with TDF and their infants did not result in serious adverse events that are statistically different as compared to the women who did not receive any treatment., Conclusion: Treatment of HBV infected pregnant women with TDF can effectively and safely prevent the perinatal transmission of chronic hepatitis B., (Copyright © 2020. Publicado por Elsevier España, S.L.U.)

Objective: Since the discovery of the SARS-CoV-2 virus, the polymerase chain reaction technique (RT-PCR) has become the fundamental method for diagnosing the disease in its acute phase. The objective is to describe the demand-based series of RT-PCR determinations received at a Microbiology Service at a third-level reference hospital for a health area for three months spanning from the onset of the epidemic by SARS-CoV-2., Methods: A retrospective analysis of the total of the RT-PCR requested in the Microbiology Service analyzed from 02/25/2020 to 05/26/2020 (90 days) has been carried out. They have been grouped by epidemiological weeks and by the petitioner service. A descriptive analysis was carried out by age, gender and number of requests for each patient. In the tests carried out, a confidence level of 95% (p <0.05) was considered significant., Results: A total of 27,106 requests was received corresponding to 22,037 patients. Median age 53.7 (RIC 40.9-71.7) years, women: 61.3%. Proportion of patients with any positive RT-PCR: 14%. Of the total requests for RT-PCR, positive 3,710. Week 13 had the highest diagnosis performance (39.0%). The primary care has been the service thar has made the most requests (15,953). Patients with 3 or more RT-PCR: 565, of them, 19 patients had a positive result after previously having a negative one., Conclusions: Requests have been increasing depending on the evolution of the epidemic. The RT-PCR has a high diagnostic performance in the phases of highest contagiousness and / or transmissibility of the virus., (©The Author 2020. Published by Sociedad Española de Quimioterapia. This article is distributed under the terms of the Creative Commons Attribution-NonCommercial 4.0 International (CC BY-NC 4.0)(https://creativecommons.org/licenses/by-nc/4.0/).)

Introduction: The results of mandatory confinement have been detrimental in several respects. Nonetheless, they have resulted in reducing the number of active cases of COVID-19. Chile has begun the de-escalation and needs to know the best time to end the restrictions., Objective: We discuss the best conditions and guarantees for the end of compulsory confinement., Methods: This study is based on a trend model with prediction estimation. The data of the variables of interest were subjected to linear regression studies to determine the curve that best explained the data. The coefficient of determination, the standard deviation of y in x, and the confidence interval of the observed curve were estimated. The trend curve was chosen in accordance with the regression estimates., Outcomes: It was found that all dependent variables tended to decrease over time in a quadratic fashion, except for the new cases variable. In general, the R2 and MAPE estimates are satisfactory, except for the variable number of PCR tests per day., Conclusions: Gradual and cautious steps should be taken before ending mandatory confinement. In the current de-escalator, daily PCR tests should be increased, maintaining vigilance on indicators of incidence, prevalence, and positivity of PCR tests. Evidence suggests with some degree of confidence that mandatory confinement could be safely lifted as of August 30, 2020. Long-term preparations must be made to contain future waves of new cases.

Introduction: The use of Cannabis continues to increase worldwide, especially among adolescents. This use overlaps with cigarette smoking and other illicit and licit drugs and s associated with depressive symptoms and suicide risk. In our national context, little is known about the relationship between Cannabis use and suicide risk. Objective: To evaluate the association between Cannabis use and elevated suicide risk in high school adolescents in Santa Marta, Colombia. Materials and methods: We conducted a cross-sectional study with a probabilistic sample of high school students between 13 and 17 years of age from official and private schools. We analyzed the use of Cannabis some time in life and suicide risk was quantified using the suicide ideation scale designed by the Center for Epidemiological Studies on Depression. Scores greater than eight were categorized as a high suicide risk. The crude and adjusted opportunity ratio (OR) was estimated. Results: A total of 1,462 students participated. Their mean age was 14.4 years (SD=0.8) and 60.3% were women. The lifetime prevalence of Cannabis use was 11.6% (95%CI: 10.0-13.2) and 13.3% of the students reported high suicide risk (95%CI: 11.6-15.0). Cannabis consumption was associated with high suicide risk adjusted by other variables (OR=1.88; 95%CI: 1.23-2.88). Conclusions: Cannabis use was associated with high suicide risk in high school adolescents in Santa Marta, Colombia. Other variables should be studied in order to further examine this association.

Introduction: The sexually transmitted infection caused by Chlamydia trachomatis is the most common of bacterial etiology in the world. Although it can be asymptomatic in most cases, it can produce several reproductive health problems in women such as cervicitis, endometritis, and salpingitis. Despite its importance, the epidemiological data on this infection is insufficient in Medellín. Objective: To determine the prevalence of C. trachomatis in women from Medellín, identify possible risk factors, and evaluate its relationship with the human papillomavirus infection (HPV). Materials and methods: We conducted a multicenter cross-sectional study to detect C. trachomatis infection in 1,282 women using PCR and the LightMix 480 HT CT/NG™ commercial kit (Roche, Basel, Switzerland). Results: The total prevalence of C. trachomatis infection was 4.1% (95% CI: 2.9-5.3). We found an association between the presence of the infection and age, cigarette consumption, and the use of hormonalcontraceptives. Conclusion: The prevalence of the infection is similar to that reported in other parts of the world with young women being the most affected population. No relation was found with the presence of HPV.

Introduction: The value of the P300 cognitive event-related potential in the diagnosis of Alzheimer subtype neurocognitive disorders is still incipient. Recent studies suggest that combining it with neuropsychological tests by cognitive domains would allow an objective and early characterisation of the cognitive impairment in its initial stages., Aims: To characterise the electrophysiological patterns in the P300 potential that obtain a discriminatory value for the diagnosis and classification of the neurocognitive disorders with a possible Alzheimer-type aetiology., Subjects and Methods: This study examines 39 patients classified, according to the DSM-5, with possible Alzheimer-type minor and major neurocognitive disorders, aged between 50 and 85 years, and 53 control subjects with normal cognitive functions. The P300 potential is registered in the auditory mode, oddball paradigm and centroparietal recording., Results: P300 latency is significantly prolonged in subjects with neurocognitive disorder; there are significant differences in the mean values and confidence intervals between healthy controls and patients. No significant differences are obtained in P300 latency between groups with minor and major neurocognitive disorder. The mean amplitude value decreases in neurocognitive disorder, and the P300 amplitude logarithm of the control groups and those with minor and major neurocognitive disorder reaches significantly different mean values and confidence intervals., Conclusions: The parameters quantified in the P300 potential can be used as complementary biomarkers to classify the presence and level of cognitive dysfunction with a possible Alzheimer-type aetiology.

Introduction: Breast cancer is a serious neoplasm that originates in mammary tissues whose treatment with chemotherapy seems to generate significant changes in the quality of life. Objective: To determine the risk factors associated with health-related quality of life in women with breast cancer under chemotherapy in Cali, Colombia. Materials and methods: We conducted an observational, cross-sectional study with analytical components in a sample of 80 female patients using the QLQ-C30 questionnaire for cancer, and the QLQ-BR23 for breast cancer, as well as sociodemographic and clinical information. We performed a logistic regression analysis to determine associated risk factors through adjusted OR and 95% CI; the quality of life was classified using the QLQ-BR23. Results: The most relevant symptoms were fatigue, insomnia, and hair loss. Physical functionality, feelings of pleasure, and sexual activity were reduced. The factors associated with low quality of life were mammary symptoms (adjusted OR= 5.5; 95% CI: 1.2-24.8; p = 0.038), systemic therapy side effects (adjusted OR = 7.3; IC95%: 2.6-22.1; p = 0.012), lower sexual pleasure (adjusted OR = 1.8; IC95%: 1.2-11.8; p = 0.027) and reduction of expectations about the future (adjusted OR = 4.2; IC95%: 1.1-17.8; p = 0.045). Conclusions: The quality of life in women with breast cancer and under chemotherapy was mainly affected by the side effects of the therapy; the most relevant signs and symptoms identified were hair loss, insomnia, and fatigue besides breast symptoms, lower physical functionality, and decreased sensation of sexual pleasure. We recommend intervention strategies aimed at improving the quality of life and the physical and emotional care of these patients.

The objective of this study was to estimate the prevalence of self-care management practices - both with and without medication - in elderly hypertensive and diabetic patients in Campinas, Brazil, in three periods. Data from health surveys conducted in three periods 2001-2002, 2008-2009 and 2014-2015 were analyzed. The prevalence of hypertension, diabetes, the continuous use of medication, and all behavioral practices showed an overall increase in the period analyzed, with a significant drop in both the non-regular use of medications and routine doctor visits on the part of individuals without a private health plan. The results evidenced advances in diet-related practices among individuals without health plans as well as those who reported having healthcare coverage, highlighting improvements in drug treatment and physical activity. Adherence to medication and health behaviors for the management of morbidities was shown to be consistent in the period evaluated. These indicators reinforce the need to maintain and expand policies directed at health education and pharmaceutical assistance in the country.

Background: Alcohol consumption is a risk factor for many health problems. Mortality from causes of death wholly attributable to alcohol consumption by sex and income level was studied and trends in the 1993-2017 period were analyzed in Navarre (Spain)., Methods: Deaths due to alcohol-induced mental disorders, dependence and abuse, alcoholic cardiomyopathy, alcoholic cirrhosis and other alcoholic liver diseases, and accidental alcohol poisoning were selected through codes ICD-9 and ICD-10. Annual income that determines copayment level was used as an indicator of socioeconomic status. Mortality rates adjusted to the European standard population were calculated using the direct method and joinpoint regression was used to evaluate the temporal trend., Results: A total of 441 deaths were recorded in the population aged 35-79 years. It highlights liver cirrhosis as the most common cause (77,5%). Death rates in men were ten and five times higher than in women in 1993-1997 and 2013-2017 periods, respectively. Compared to men with incomes above 18,000 €, mortality rates were five times higher in the population with incomes below 18,000 €. No statistically significant changes were observed in the trend of mortality rates throughout the period studied., Conclusions: Mortality by causes of death wholly attributable to alcohol has not decreased in Navarre in the last three decades, it is higher in men than in women and in the population with lower incomes.

Introduction and Objectives: Aim of this study is to determine the setting, causes, and the harm of medication errors (ME) which are notified by Primary Health Care., Material and Methods: Setting: Primary Care Regional Health Service of Madrid. 2016., Design: Descriptive and cross-sectional study., Participants: All ME (1,839) which were notified by Primary Care Centres by notification system of safety incidents between January 1st 2016 and November 17th 2016., Main Measurements: Setting, real harm, potential harm, and cause of error. These items were classified by one researcher. Concordance was checked with another researcher., Results: Just under half (47%) (95% CI: 44.8%-49.3%) of ME occurred in Primary Care Centre, 26.5% (95% CI: 24.5%-28.6%) of ME were patient medication errors, and 27.5% (95% CI: 24.1%-30.8%) of ME were potential severe harm errors. Prescribing errors were the cause of most ME in Primary Care Centre [27.4% (95% CI: 24.4%-30.4%)]. Communication between patients and doctors were the cause of most patient medication errors [66% (95% CI: 61.8%-70.2%)]. Patient mistakes and forgetfulness were also causes of patient medication errors., Conclusions: Half of all mediation errors hppened at Primary Care Center while one quarter of them were patient medication errors. One quarter of all ME were potential severe harm errors. The main causes were prescribing errors, failure of communication between patients and doctors, and patient mistakes and forgetfulness. Prescribing aid systems, communication improvements and patients aids should be implemented., (Copyright © 2019 The Authors. Publicado por Elsevier España, S.L.U. All rights reserved.)