Medical Statistics

espanolEn la presente investigacion se propone una nueva metodologia para la construccion de indicadores sinteticos de sostenibilidad, de forma que se tengan en cuenta las necesidades y aspiraciones de todos los implicados en el desarrollo del sector, a traves de indicadores provenientes de fuentes estadisticas de informacion y de aquellos que proporcionan informacion sobre los juicios de valor de los pobladores locales y los turistas. El estudio se lleva a cabo en las zonas donde se desarrolla el turismo de naturaleza en la Republica de Cuba. EnglishIn the present investigation, a new methodology is proposed for the construction of sustainability composite indicators, with the purposed that all necessities and goals to the involved people of the sector development have been taken into account by means of indicators originated from source of statistical information and those that give information about the value opinions of local inhabitants and tourists. The study takes place in zo...

Originating in China, the Coronavirus has reached the world at different speeds and levels of strength. This paper provides some initial understanding of some driving factors and their consequences. Since transmission requires people, the human factor behind globalization is essential. Globalization, a major force behind global wellbeing and equality, is highly associated with this factor. The analysis investigates the impact globalization has on the speed of initial transmission to a country and on the size of initial infections in the context of other driving factors. Our cross-country analysis finds that measures of globalization are positively related to the spread of the virus, both in speed and size. However, the study also finds that globalized countries are better equipped to keep fatality rates low. The conclusion is not to reduce globalization to avoid pandemics, but to better monitor the human factor at the outbreak and to mobilize collaboration forces to curtail diseases.

The aim of this study was to assess the relationship between self-image in eating disorders and age, duration and severity of the disorder, comorbidity, depressiveness and self-evaluation of eating problems. The results of the Offer self-image questionnaire for adolescents (QSIA) were compared in four groups: anorexia nervosa restrictive subtype (ANR, n: 47), anorexia nervosa binge/purge subtype (ANBP, n: 16), bulimia nervosa (BUL, n: 34) and eating disorders NOS (EDNOS, n: 19). The control group was age matched female pupils (NOR, n = 76). The Kruskal-Wallis test revealed significant differences between the age of patients from the ANR (16.34, SD 1.58) and BUL (17.56, SD 0.96) groups (p = .008). The self-image of schoolgirls from the NOR group was on most scales significantly better than the self-image of girls from clinical groups. On four scales differences between the (better) self-image in the ANR group and that in the BUL group were observed. Next, a cluster analysis using a g...

Башкуев В. Ю. НЕТРИВИАЛЬНЫЙ ПОДХОД, ИЛИ КАК ВРАЧИ-БОЛЬШЕВИКИ ЛЕЧИЛИ КОРОЛЕЙ. СОВЕТСКАЯ МЕДИЦИНА НА АРАВИЙСКОМ ПОЛУОСТРОВЕ В 1920-1930-е ГОДЫ ФГБУН «Институт монголоведения, буддологии и тибетологии Сибирского отделения Российской академии наук», 670047, г. Улан-Удэ

This work outlines the role played in Italy by statisticians, together with medical doctors, to draw politicians' attention to the population healthcare to further encourage national development. This topic becomes particularly relevant thanks to the "statistics factory" at the MAIC's (Ministry for Agriculture, Industry and Commerce) Directorate General for Statistics which existed from the Italian Unification (1861) till the end of the 19th century. Moreover, under the supervision of Luigi Bodio, a scholar and a master with a wide net of relations with other scientists, MAIC becomes an interesting vantage point for observing how healthcare issues became a substantial element of the Italian national building process with reference to foreign counterparts.

Background-The fifth Millennium Development Goal (MDG 5) established the goal of a 75% reduction in the maternal mortality ratio (MMR; number of maternal deaths per 100 000 livebirths) between 1990 and 2015. We aimed to measure levels and track trends in maternal mortality, the key causes contributing to maternal death, and timing of maternal death with respect to delivery. Methods-We used robust statistical methods including the Cause of Death Ensemble model (CODEm) to analyse a database of data for 7065 site-years and estimate the number of maternal deaths from all causes in 188 countries between 1990 and 2013. We estimated the number of pregnancy-related deaths caused by HIV on the basis of a systematic review of the relative risk of dying during pregnancy for HIV-positive women compared with HIV-negative women. We also estimated the fraction of these deaths aggravated by pregnancy on the basis of a systematic review. To estimate the numbers of maternal deaths due to nine different causes, we identified 61

This study proposes a Bayesian joint model with extended random effects structure that incorporates nested repeated measures and provides simultaneous inference on treatment effects over time and drop-out patterns. The proposed model includes flexible splines to characterize the circadian variation inherent in blood pressure sequences, and we assess the effectiveness of an intervention to resolve pediatric obstructive sleep apnea. We demonstrate that the proposed model and its conventional two-stage counterpart provide similar estimates of nighttime blood pressure but estimates on the mean evolution of daytime blood pressure are discrepant. Our simulation studies tailored to the motivating data suggest reasonable estimation and coverage probabilities for both fixed and random effects. Computational challenges of model implementation are discussed.

The authors concluded that infliximab was the most effective treatment for moderate to severe psoriasis, followed by ustekinumab, adalimumab, etanercept and efalizumab. The review was generally well conducted. Only short-term outcomes were analysed, so the long-term effects of the treatments was not known. Apart from this, the results of the review are likely to be reliable. To compare the effectiveness of all currently available biologic agents for the treatment of moderate to severe psoriasis. MEDLINE and EMBASE were searched from January 1995 to October 2008. The Cochrane Library was also searched. Reference lists of included studies were checked. Abstracts from major dermatology meetings were searched to identify unpublished studies. Randomised controlled trials for treatment of plaque-type psoriasis in adults were eligible. Trials had to be placebo controlled or head-to-head comparisons of monotherapy. Eligible treatments were adalimumab, efalizumab, etanercept, infliximab, and ustekinumab. All treatments had to be given at the approved dose. Most included trials were of 12 weeks duration (range 10 to 30 weeks). Disease severity was similar across trials; mean duration of disease was 18 to 22 years. Most patients had received prior systemic or phototherapy treatment. The mean age of patients ranged from 44 to 47 years; 60 to 70% were men. Most patients were Caucasian. Study selection was performed by two reviewers. Twenty trials, with over 10,000 patients, were included in the review; sample sizes ranged from 22 to 1,230 patients. There were three trials of adalumimab, five of efalizumab, five of etanercept, four of infliximab, and three of ustekinumab; only one trial was a comparison of treatments, the rest were placebo controlled. All trials were of high quality (Jadad scores ranged from 3 to 5).

The article presents design of historical study of the Russian pharmaceutical market, setting timeline in the nineties-the time of formation of social and cultural characteristics of this phenomenon. At the same time, the authors return to the post-Soviet period and the nineties to see starting positions as well as mutations of original idea. The article is structured by the framework format of dissertation abstract. This frame contains the following elements: research questions, assessment of state of research field, working hypotheses, the author's vision of social and scientific significance of the study being conducted and observations made. The definition of the research genre as dystopia is explained by its deconstruction of the palimpsest of memory testimonies of pharmaceutical market actors. K e y w o r d s : history of markets; history of medicine; economic history; Russian pharmaceuticals. For citation: Vishlenkova E. A., Zatravkin S. N. The (un)governed market, or The history of Russian Pharma. A dystopia.

Ο στατιστικολόγος Francis Anscombe, το 1973, παρήγαγε 4 διαφορετικά σύνολα δεδομένων, που όμως είχαν σχεδόν πανομοιότυπα στατιστικά χαρακτηριστικά. Τα 4 αυτά σύνολα δεδομένων, κατόπιν τα τοποθέτησε σε άξονες x και y , όπου παρά την ομοιότητά τους σε καίριες στατιστικές παραμέτρους, είχαν εντελώς διαφορετική εικόνα στο διάγραμμα x και y. Κάθε σύνολο έχει σχεδόν: Ίδια μέση τιμή (mean) για τις τιμές x και y. Ίδιο συντελεστή συσχέτισης (correlation). Ίδια ευθεία παλινδρόμησης (linear regression line). Ίδια διακύμανση. Ωστόσο, όταν τα απεικονίσουμε σε διάγραμμα διασποράς (scatter plot), βλέπουμε ριζικά διαφορετικά σχήματα: Παρά, λοιπόν, τα σχεδόν πανομοιότυπα στατιστικά, μπορεί η ιατρική κλινική και εργαστηριακή εικόνα να είναι εντελώς διαφορετική όταν οπτικοποιήσουμε τα δεδομένα μας. Είναι προφανές, ότι αυτές οι οπτικοποιήσεις θα μπορούσαν να αντιστοιχούν σε εντελώς διαφορετικές κλινικές και παθοφυσιολογικές καταστάσεις, αφού φαίνεται λόγου χάρη μια γραμμική σχέση στο διάγραμμα 1, ενώ στο διάγραμμα 4 η εικόνα δείχνει εντελώς διαφορετική, με ένα outlier να επηρεάζει το σύνολο. Στο διάγραμμα 2, φαίνεται ότι τα δεδομένα έχουν «οροφή» και αυτό είναι εντελώς διαφορετικό παθοφυσιολογικά από μια απλή γραμμική σχέση με τα ίδια ακριβώς στατιστικά. Το Anscombe's Quartet, μας δείχνει, λοιπόν, πέραν πάσης αμφιβολίας, ότι:

Disease risk prediction tools are used for population screening and to guide clinical care. They identify which individuals have particularly elevated risk of disease. The development of a new risk prediction tool involves several methodological components including: selection of a general modelling framework and specific functional form for the new tool, making decisions about the inclusion of risk factors, dealing with missing data in those risk factors, and performing validation checks of a new tool’s performance. There have been many methodological developments of relevance to these issues in recent years. Developments of importance for disease detection in humans were reviewed and their uptake in risk prediction tool development illustrated. This review leads to guidance on appropriate methodology for future risk prediction development activities.

Introduction: According to global health estimates from the World Health Organization (WHO) injuries represent 8% of world deaths. There are systematic reviews that relate lactate and mortality in trauma patients but do not focus on multiple trauma patients. Objective: To determine if elevated lactate is a mortality factor in multiple trauma patients. Methodology: A systematic review and meta-analysis of observational studies were carried out. The search was carried out in 4 databases: PUBMED, Embase, Scopus, and Web of Science. Data were pooled using a random effects model and summary statistics were calculated using odds ratios (ORs) with their respective 95% confidence intervals (95% CI). Results: Nine studies were included (n=5302). A significant association was found between elevated admission lactate with mortality (OR: 1.80; 95% CI 1.11 to 2.91) and 72-hour mortality (OR: 1.24; 95% CI 1.02 to 1.50). No statistically significant association was found for the analysis of elevat...

Introduction: Noise-induced hearing loss has been implicated in the genesis of several chronic conditions; however, its behavior concerning hypertension still raises doubts about it. Objective: to determine the association between hearing loss due to exposure to noise and the presence of hypertension in a sample of Peruvian workers. Methods: Cross-sectional analytical study. Secondary analysis of the occupational database of a Medical center in Lima, Peru. hypertension was measured by self-report and clinical method. Hearing loss was classified as none, mild, moderate and severe. For the regression analysis, Poisson was performed with robust variance, obtaining crude (PRc) and adjusted (PRa) prevalence ratios. Results: We worked with a total of 1987 participants. The prevalence of hypertension was 15.40% and hearing loss was 36.39%. For the multivariate regression analysis, a statistically significant association with hypertension was found in those with mild hearing loss (PRa=1.52;...

Δεν υπάρχει αμφιβολία ότι πλήθος επιστημονικών εργασιών στην Ιατρική, δεν είναι δυνατόν να αναπαραχθούν, αν και το ακριβές ποσοστό ποικίλλει ανάλογα με την ερευνητική προσέγγιση όπως αναφέρει ο J. Ioannidis [1]. Τα αίτια του φαινομένου είναι πάρα πολλά και ανάμεσά τους η νοοτροπία "publish or perish", η κακή χρήση της Στατιστικής, σε συνδυασμό με την πληθώρα περιοδικών-predator journals / paper mills που δημοσιεύουν σχεδόν οτιδήποτε έναντι αμοιβής. Όμως, όπως θα δειχτεί παρακάτω, η Συχνοτική Προσέγγιση στην Στατιστική, έχει ενδογενή μειονεκτήματα που δημιουργούν μείζονα προβλήματα στην επιστημονική έρευνα. Πέραν, λοιπόν, της στενής της σχέσης με την ψευδοεπιστήμη της Ευγονικής [2], η Συχνοτική Προσέγγιση παρουσιάζει πλήθος ενδογενών μεθοδολογικών αδυναμιών:

Many investigations have shown that artemisinin-based combination therapies are effective in the treatment of uncomplicated malaria and that they do not increase parasite resistance to treatment as much as treatment with single substance. We study the relation between some biological covariates and the time to first recurrence of malaria for children treated for malaria in a clinical trial. One group received artesunate plus sulfadoxine-pyrimethamine and the other only sulfadoxine-pyrimethamine. We consider the event malaria-free for the first 42 (and 84) days. We use logistic regression models for the analyses. The main results show that the probability of no recurrence is higher if the parasite density in the blood is high. The results are inconclusive for other explanatory biological variables. The infecting parasites having genes that indicate resistance, gave different results at the two different treatment centres. There was no appreciable difference in the effects of treatmen...

Background: A review of the health behavior literature on the statistical modeling of days of physical activity (PA) indicates that in many instances linear regression models have been used. It is inappropriate statistically to model a count dependent variable such as days of physical activity with Ordinary Least Squares (OLS). Many count variables have skewed distributions, and, also, have a preponderance of zeroes. Count variables should not be treated as continuous and unbounded. If OLS is used, estimations of the regression will frequently turn out to be inefficient, inconsistent and biased, and such outcomes could well have incorrect impacts on health programs and policies. Methods: We considered three statistical methods for modelling the distribution of days of PA data for respondents in the 2013 Health Information Trends Survey (HINTS). The three regression models analyzed were: Ordinary Least Squares (OLS), Negative Binomial (NBRM), and Zero-inflated Negative Binomial (ZINB...

Background-The fifth Millennium Development Goal (MDG 5) established the goal of a 75% reduction in the maternal mortality ratio (MMR; number of maternal deaths per 100 000 livebirths) between 1990 and 2015. We aimed to measure levels and track trends in maternal mortality, the key causes contributing to maternal death, and timing of maternal death with respect to delivery. Methods-We used robust statistical methods including the Cause of Death Ensemble model (CODEm) to analyse a database of data for 7065 site-years and estimate the number of maternal deaths from all causes in 188 countries between 1990 and 2013. We estimated the number of pregnancy-related deaths caused by HIV on the basis of a systematic review of the relative risk of dying during pregnancy for HIV-positive women compared with HIV-negative women. We also estimated the fraction of these deaths aggravated by pregnancy on the basis of a systematic review. To estimate the numbers of maternal deaths due to nine different causes, we identified 61

Major Depressive Disorder (MDD) is a major public health problem in Nigeria and has severely devastating effects on the elderly. Previous studies on MDD among elderly Nigerians have utilized cross sectional designs which are descriptive in nature and have not investigated differences in setting and time-occurrence of MDD. Therefore this study employed a random effect logistic regression model to determine the relative effects/contributions of individual and environmental factors in the occurrence of MDD. A secondary analysis of a four-year longitudinal data from the Ibadan Study of Ageing was conducted. A total of 2,149 elderly Nigerians participated in the study between 2003 and 2009. The Geriatric Depression Scale was used to assess MDD and consequently classified as "present" for scores ranging from 10 to 30 and "absent" for scores ranging from 0 to 9. A random effect logistic regression model was fitted to determine factors predicting MDD. Odds ratios (OR), 9...

The authors explain the source peculiarity of medical statistics in Russia between the eighteenth and first half of the nineteenth centuries and identify the possibilities and limitations of its use for studying social history and the history of science. The features of the quantitative evidence at that time – them being fragmented, heterogeneous, and expressed in absolute numbers – prompted the authors to turn to the history of the organization of statistical studies in the Russian Empire. The estimation of information value and the discursive nature of health and morbidity statistics were performed based on the analysis of administrative documents (Polnoe Sobranie Zakonov – Complete Collection of Laws, ministerial prescriptions), accounts of medical administrations, uyezd doctors, and medical professors (military-historical and historical archives of Astrakhan, Moscow, Riga, and Vilnius). Based on the presumption that target setting, i. e. the purpose of quantitative indicators, d...

Background It is still difficult to prevent partial or full-thickness flap necrosis. In this study, the effects of a cream containing menthol and methyl salicylate on the viability of randompattern skin flaps were studied. Methods Forty female Sprague-Dawley rats were divided into two equal groups. Caudally based dorsal random-pattern skin flaps were elevated, including the panniculus carnosus. In the study group, 1.5 mL of a cream containing menthol and methyl salicylate was applied to the skin of the flap, and saline solution (0.9%) was used in the control group. Upon completion of the experiment, flap necrosis was analyzed with imaging software and radionuclide scintigraphy. Histopathological measurements were made of the percentage of viable flaps, the number of vessels, and the width of the panniculus carnosus muscle. Results According to the photographic analysis, the mean viable flap surface area in the study group was larger than that in the control group (P = 0.004). According to the scintigrams, no change in radioactivity uptake was seen in the study group (P > 0.05). However, a significant decrease was observed in the control group (P = 0.006). No statistically significant differences were observed between the groups in terms of the percentage of viable flaps, the number of vessels, or the width of the panniculus carnosus muscle (P > 0.05). Conclusions Based on these results, it is certain that the cream did not reduce the viability of the flaps. Due to its vasodilatory effect, it can be used as a component of the dressing in reconstructive operations where skin perfusion is compromised.

Estadística Descriptiva e Inferencial, Ejercicios y Soluciones es un manual que condensa años de experiencia docente en cursos de grado y posgrado en estadística, ofreciendo un enfoque claro y estructurado para estudiantes, profesionales y académicos. Cada capítulo introduce de manera precisa un método estadístico, seguido de explicaciones paso a paso que permiten no solo su comprensión teórica, sino también su aplicación práctica a través de ejercicios resueltos. El libro se distingue por adaptar los ejercicios a casos reales de áreas como Administración de Empresas, Marketing y Negocios Digitales, lo que lo convierte en una herramienta indispensable para quienes buscan tomar decisiones basadas en datos
Los ejercicios propuestos, con sus respectivas soluciones, permiten evaluar y consolidar conocimientos de forma autónoma. Diseñado tanto para el aprendizaje autodidacta como para complementar la enseñanza formal, este manual abarca conceptos fundamentales y avanzados, desde la organización de datos y medidas de tendencia central hasta análisis inferencial y aplicación de modelos estadísticos.
La claridad pedagógica del texto garantiza una experiencia de aprendizaje efectiva y accesible, incluso para quienes no cuentan con antecedentes sólidos en estadística. Este libro es el compañero ideal para quienes desean dominar las herramientas estadísticas que son esenciales en la toma de decisiones informadas en entornos empresariales y digitales.

Human subjects research is a cornerstone of scientific advancement in medicine and public health. It is a rigorously regulated process requiring adherence to ethical standards and methodological precision. This paper explores the fundamental definitions of human subjects research and the regulatory landscape, particularly referencing the U.S. Department of Health and Human Services Code of Federal Regulations (45 CFR 46). The discussion further classifies research methodologies into quantitative, qualitative, and mixed-methods designs, emphasizing their unique roles and applications. Issues of concern, such as formulating a viable research question and selecting the appropriate study design, are critically analyzed. The paper also underscores the clinical significance of research findings, illustrating their impact on evidence-based medicine and public health policy. Through systematic inquiry and ethical conduct, research not only contributes to scientific knowledge but also directly benefits patients and communities.

espanolLa construccion de indicadores sint´eticos basados en el criterio del beneficio de la duda se caracterizan por determinar de manera endogena el vector de ponderaciones con el que se agregaran los indicadores individuales. El presente trabajo propone un modelo de agregacion que intenta salvar las principales criticas realizadas a este tipo de procedimientos: la seleccion de vectores diferentes para cada alternativa, lo que dificulta la comparacion de los resultados finales, y la aparicion de multiples empates. Para ello, se propone un procedimiento que, manteniendo la esencia de los modelos de agregacion basados en DEA, concluye determinando un vector de pesos comun para todas las alternativas y en el que la discriminacion entre los valores finales del indicador sintetico se incluye como objetivo del procedimiento. EnglishComposite indicators constructed on the basis of the benef t of the doubt criterion are charac-terized by endogenously determined vectors of weights. In this...

Background-The fifth Millennium Development Goal (MDG 5) established the goal of a 75% reduction in the maternal mortality ratio (MMR; number of maternal deaths per 100 000 livebirths) between 1990 and 2015. We aimed to measure levels and track trends in maternal mortality, the key causes contributing to maternal death, and timing of maternal death with respect to delivery. Methods-We used robust statistical methods including the Cause of Death Ensemble model (CODEm) to analyse a database of data for 7065 site-years and estimate the number of maternal deaths from all causes in 188 countries between 1990 and 2013. We estimated the number of pregnancy-related deaths caused by HIV on the basis of a systematic review of the relative risk of dying during pregnancy for HIV-positive women compared with HIV-negative women. We also estimated the fraction of these deaths aggravated by pregnancy on the basis of a systematic review. To estimate the numbers of maternal deaths due to nine different causes, we identified 61

Background: Physical activity brings improvements in the quality of life in all individuals, disabled and non-disabled. There is little evidence in the literature of inclusive physical activity in which disabled and non-disabled people participate at the same level. Objectives: The study aimed to demonstrate the effectiveness of an inclusive training program, structured in such a way as to encourage physical activity for all participants with and without disabilities, in improving body composition, explosive strength, and endurance. Methods: A sample of twenty-four subjects (mean age: 24.09±3.92 years), 12 disabled and 12 non-disabled, was selected. Quantitative input and output data were recruited at 16-week intervals using a battery of tests: anthropometric measurements, Vertec Squat Jump test, and Yoyo Endurance Test. During the 16 weeks, all participants followed an appropriately structured training program in four mesocycle without any differences. Input and output data were co...

Background: The risk of falls is a major cause of disability in older adults. A single fall, for the elderly, increases the risk of frequent falls and often causes an increased fear of falling again, which can become debilitating. Objectives: The purpose of the present study was to test the effects of 12 weeks of proprioceptive training on the static and dynamic balance of older adults who have experienced at least one fall without compromising consequences. Method: The sample consisted of older adults, aged 60 to 80 years, randomly divided into two groups: an experimental group, which followed a proprioceptive training protocol at a physiotherapy studio, and a control group, which did not observe any treatment. Static and dynamic balance assessment was performed pre-and post-intervention. The tests administered were the Berg Balance Test for the evaluation of static balance, and the Four-Square Step Test, for dynamic balance. A questionnaire to assess confidence and fear of falling...

Statistics plays a pivotal role in healthcare by guiding decision-making, enhancing research methodologies, and improving patient outcomes. This paper explores the fundamental aspects of statistics, its applications in biostatistics, and the structured processes of data collection, organization, analysis, and interpretation. Key issues encountered in healthcare settings, such as data integrity, ethical concerns, and misconceptions about statistical analysis, are examined. The clinical significance of utilizing statistical findings for practical decision-making is highlighted, emphasizing the importance of interprofessional collaboration. Ultimately, this work underscores the critical need for healthcare professionals to develop statistical literacy to ensure accurate data utilization and improved healthcare delivery.

Introduction: Despite the growing awareness of the importance of knowledge in biostatistics, many investigations worldwide have found that medical students have a poor understanding of it. Objective: To determine the percentage of Peruvian medical students with sufficient biostatistics knowledge and the associated factors. Methods: Cross-sectional analytical study. Application of a virtual survey to medical students from different faculties in Peru. Results: 56.46% of medical students have insufficient knowledge of biostatistics. A statistically significant association was found for those who were 25 years of age or older (aPR: 1.195; 95% CI 1.045 - 1.366; p=0.009); being between the 9th and 12th semester (aPR: 1.177; 95% CI 1.001 - 1.378; p=0.037) and medical internship (aPR: 1.373; 95% CI 1.104 - 1.707; p=0.004); take an external course in biostatistics, epidemiology or research (aPR: 4.016; 95% CI 3.438 - 4.693; p<0.001); having read more than 12 articles per year (aPR: 1.590;...

The population surviving to old age in sub-Saharan Africa (SSA) is increasing rapidly in consonance with the rest of the world. Nevertheless, the sub-region offers unique challenges to survival across the lifespan. The determinants of health and ageing in SSA are thus likely different from those in higher income countries. The need to explore pressing epidemiological and health service challenges of older people living in SSA in the context of multiple social changes and rapid ageing of the population provided the rationale for the Ibadan Study of Ageing (ISA). This article appraises ISA findings in relation to late-life depression. It concludes that healthcare policies in SSA need to deliberately prioritise the treatment of depression and other mental health problems in late-life in order to stem the neglect of older people's mental health in the region.

We already showed the superiority of imputation of missing data (via Multivariable Imputation via Chained Equations (MICE) method) over exclusion of them; however, the methodology of MICE is complicated. Furthermore, easier imputation methods are available. The aim of this study was to compare them in terms of model composition and performance. Three hundreds and ten breast cancer patients were recruited. Four approaches were applied to impute missing data. First we adopted an ad hoc method in which missing data for each variable was replaced by the median of observed values. Then 3 likelihood-based approaches were used. In the regression imputation, a regression model compared the variable with missing data to the rest of the variables. The regression equation was used to fill the missing data. The Expectation Maximum (E-M) algorithm was implemented in which missing data and regression parameters were estimated iteratively until convergence of regression parameters. Finally, the MI...

Introduction: Imputation of missing data and selection of appropriate risk function are of importance . Sometimes a variable with continuous nature will be offered to the regression model as an ordinal variable. Our aim is to investigate whether to offer the continuous form of the variable to the imputation phase and its ordinal from to the modeling phase, or whether to offer the ordinal version to both phases. Material and Methods: The outcome and main variable of interest was use of diet as a body change approach, and Body Mass Index (BMI). We randomly deleted 10%, 20%, and 40% of BMI values. In strategies 1 and 2, BMI was offered to the imputation phase as a continuous (BMIC) and ordinal variable (BMIO). Missing data were imputed using linear and polytomous regression respectively. In strategy 1, after imputation, BMIC was categorized (named BMICO) and offered to the modeling phase. In strategy 2, after imputation of BMIO values, this variable was offered to the logistic model (n...

Having investigated the combined use of arutimol and travatan the authors of the article came to the
conclusion that now it is the most effective way of hypotensive therapy in the patients with the primary open-angle
glaucoma allowing to achieve optimal intraocular pressure in the vast majority of patients, avoidance from
operative intervention.

This paper presents a discussion on the mathematical properties of the inverse Burr distribution. The application of the distribution was subjected to two-lifetime data sets and some measures of goodness-of-fit such as the Akaike Information Criterion (AIC), Bayesian Information Criterion (BIC), and Komolgorov-Smirnov (K-S) test statistics were considered to examine its flexibility in modeling lifetime data and the superiority over other well-known distributions. Results obtained from the two-lifetime data sets reveal that the inverse Burr distribution is an appropriate model in fitting the lifetime data sets and has superiority over other distributions considered.

Background-The fifth Millennium Development Goal (MDG 5) established the goal of a 75% reduction in the maternal mortality ratio (MMR; number of maternal deaths per 100 000 livebirths) between 1990 and 2015. We aimed to measure levels and track trends in maternal mortality, the key causes contributing to maternal death, and timing of maternal death with respect to delivery. Methods-We used robust statistical methods including the Cause of Death Ensemble model (CODEm) to analyse a database of data for 7065 site-years and estimate the number of maternal deaths from all causes in 188 countries between 1990 and 2013. We estimated the number of pregnancy-related deaths caused by HIV on the basis of a systematic review of the relative risk of dying during pregnancy for HIV-positive women compared with HIV-negative women. We also estimated the fraction of these deaths aggravated by pregnancy on the basis of a systematic review. To estimate the numbers of maternal deaths due to nine different causes, we identified 61

A well-known nonparametric alternative to a student t-test is the Wilcoxon signed-rank test from the library of classical statistic tests. The test is frequently used in decision-making situations when it is necessary to compare the means of two populations using two matched samples or test the mean of a population based on a sample of data. The interval-valued data frequently exhibit uncertainty and imprecision and frequently result from unclear and ambiguous circumstances. This research developed a neutrosophic Wilcoxon signed-rank test for analysing sample observations or groups of observations by modifying the classical Wilcoxon signed-rank test under uncertainty where the assumption of normality does not hold. The proposed test was applied to a set of data related to diabetes patients. The diabetic patients' pre-and post-treatment data were collected for both determinate and indeterminate parts for one month. The findings of the study revealed that interval-valued data circumstances would be better suited for the modified Wilcoxon signed rank test. Also, the neutrosophic Wilcoxon signed-rank test used on diabetes data set revealed that the proposed test yields more accurate and appropriate results for interval-valued data whereas the classical nonparametric Wilcoxon signed-rank test would have produced false results The proposed test revealed that, at a 5% level of significance, the diabetic patients' median differences between pre-treatment and post-treatment are equal to zero. Therefore, in the presence of indeterminacy, the proposed neutrosophic Wilcoxon signed-rank test is appropriate as a substitute for the classical form of the test.

La cirugía meniscal es uno de los procedimientos más frecuentes en el campo de la cirugía ortopédica. Sin embargo, los efectos negativos en términos de estabilidad, función y desgaste a largo plazo que conlleva la falta de masa meniscal ha dado lugar a una disminución progresiva de esta práctica y del incremento correspondiente de la reparación, mediante sutura o la sustitución meniscal completa. Se revisan en este artículo el conocimiento actual acerca del trasplante meniscal alogénico y sus resultados, examinando las indicaciones, las características del aloinjerto, la técnica quirúrgica, y los resultados actuales y complicaciones.

Objectives: Hospital-based surveillance of influenza and acute respiratory infections relies on International Classification of Diseases (ICD) codes and hospital laboratory reports (Standard-of-Care). It is unclear how many cases are missed with either method, i.e. remain undiagnosed/coded as influenza and other respiratory virus infections. Various influenza-like illness (ILI) definitions co-exist with little guidance on how to use them. We compared the diagnostic accuracy of standard surveillance methods with a prospective quality management (QM) programme at a Berlin children's hospital with the Robert Koch Institute. Methods: Independent from routine care, all patients fulfilling pre-defined ILI-criteria (QM-ILI) participated in the QM programme. A separate QM team conducted standardized clinical assessments and collected nasopharyngeal specimens for blinded real-time quantitative PCR for influenza A/B viruses, respiratory syncytial virus, adenovirus, rhinovirus and human metapneumovirus. Results: Among 6073 individuals with ILI qualifying for the QM programme, only 8.7% (528/6073) would have undergone virus diagnostics during Standard-of-Care. Surveillance based on ICD codes would have missed 61% (359/587) of influenza diagnoses. Of baseline ICD codes, 53.2% (2811/5282) were nonspecific, most commonly J06 ('acute upper respiratory infection'). Comparison of stakeholder case definitions revealed that QM-ILI and the WHO ILI case definition showed the highest overall sensitivities (84%e97% and 45%e68%, respectively) and the CDC ILI definition had the highest sensitivity for influenza infections (36%, 95% CI 31.4e40.8 for influenza A and 48%, 95% CI 40.5e54.7 for influenza B). Conclusions: Disease-burden estimates and surveillance should account for the underreporting of cases in routine care. Future studies should explore the effect of ILI screening and surveillance in various age groups and settings. Diagnostic algorithms should be based on the WHO ILI case definition combined with targeted testing.

Background: Administrative healthcare databases are widely present in Italy. Our aim was to describe the current state of healthcare databases validity in terms of discharge diagnoses (according to the International Classification of Diseases, ICD-9 code) and their output in terms of research. Methods: A systematic search of electronic databases including Medline and Embase (1995-2013) and of local sources was performed. Inclusion criteria were: healthcare databases in any Italian territory routinely and passively collecting data; medical investigations or procedures at patient level data; the use of a validation process. The quality of studies was evaluated using the STARD criteria. Citations of the included studies were explored using Scopus and Google Scholar. Results: The search strategy allowed the identification of 16 studies of which 3 were in Italian. Thirteen studies used regional administrative databases from Lombardia, Piemonte, Lazio, Friuli-Venezia Giulia and Veneto. Th...

Passive smoking is now firmly established as a significant cause of morbidity and mortality. Assessment of young adults’ perceptions, understanding and knowledge of the health effects of passive smoking may promote educational endeavours to increase awareness of the passive smoking-linked health effects and to facilitate interventions. The study, therefore, assessed the perceptions of young adults in Bangladesh about the health effects of passive smoking. This cross-sectional descriptive study was conducted among 656 young adults in two districts under Dhaka division of Bangladesh. The study used a multistage cluster random sampling approach. Binary logistic regression was used for identifying the predictors of perceptions that passive smoking is harmful. The vast majority of the respondents believed that passive smoking causes illnesses but the knowledge of specific health effects was limited. Most (87.2%) respondents perceived that passive smoking causes ‘some’ or ‘a lot’ of harm ...

Background-The fifth Millennium Development Goal (MDG 5) established the goal of a 75% reduction in the maternal mortality ratio (MMR; number of maternal deaths per 100 000 livebirths) between 1990 and 2015. We aimed to measure levels and track trends in maternal mortality, the key causes contributing to maternal death, and timing of maternal death with respect to delivery. Methods-We used robust statistical methods including the Cause of Death Ensemble model (CODEm) to analyse a database of data for 7065 site-years and estimate the number of maternal deaths from all causes in 188 countries between 1990 and 2013. We estimated the number of pregnancy-related deaths caused by HIV on the basis of a systematic review of the relative risk of dying during pregnancy for HIV-positive women compared with HIV-negative women. We also estimated the fraction of these deaths aggravated by pregnancy on the basis of a systematic review. To estimate the numbers of maternal deaths due to nine different causes, we identified 61

This paper studies a spatial competition game between two rms that sell a homogeneous good at some predetermined xed price. A population of consumers is spread out over the real line, and the two rms simultaneously choose location in this same space. When buying from one of the rms, consumers incur the xed price plus some transportation costs, which are increasing with their distance to the rm. Under the assumption that each consumer is ready to buy one unit of the good whatever the locations of the rms, rms converge to the median location: there is minimal dierentiation. In this article, we relax this assumption and assume that there is an upper limit to the distance a consumer is ready to cover to buy the good. We show that the game always has at least one Nash equilibrium in pure strategy. Under this more general assumption, the minimal dierentiation principle no longer holds in general. At equilibrium, rms choose minimal, intermediate or full dierentiation, depending on this critical distance a consumer is ready to cover and on the shape of the distribution of consumers' locations.

Background-The fifth Millennium Development Goal (MDG 5) established the goal of a 75% reduction in the maternal mortality ratio (MMR; number of maternal deaths per 100 000 livebirths) between 1990 and 2015. We aimed to measure levels and track trends in maternal mortality, the key causes contributing to maternal death, and timing of maternal death with respect to delivery. Methods-We used robust statistical methods including the Cause of Death Ensemble model (CODEm) to analyse a database of data for 7065 site-years and estimate the number of maternal deaths from all causes in 188 countries between 1990 and 2013. We estimated the number of pregnancy-related deaths caused by HIV on the basis of a systematic review of the relative risk of dying during pregnancy for HIV-positive women compared with HIV-negative women. We also estimated the fraction of these deaths aggravated by pregnancy on the basis of a systematic review. To estimate the numbers of maternal deaths due to nine different causes, we identified 61

The present study was designed to assess and compare parenting stress and family burden in mothers of children with disabilities and children without disability. For this purpose, a multi group design was adopted which consisted of five groups of mothers viz. mothers of children with mental disability, mothers of children with both mental and physical disability, mothers of children with physical disability, mothers of deaf and dumb children and mothers of children without disability. Parenting stress index and family burden scale were administered on 125 mothers of children with disabilities and without disability (25mothers in each group), selected from three districts of Haryana state. For statistical analysis, t-test, simple analysis of variance and Duncan"s post hoc test were used. Results revealed that mothers of children with both mental and physical disability and mothers of children with mental disability scored significantly higher level of parenting stress and family burden compared to mothers of children with physical disability, mothers of deaf and dumb children, and mothers of children without disability.

In medical research, frequently other important determinants, correlated with the key treatment variable, are omitted from the analysis. This omission yields biased and inconsistent estimates. For example, leaving out correlated (with, say, ) determinants of Y from regressions yield biased estimates of key parameters (say ). Instrumental variable estimation solves this problem by constructing similar triangles to retrieve consistent estimates. This article illustrates the geometry of correlated regressor bias, and the simple IV geometric solution.