Percentiles de peso, talla e índice de masa corporal de escolares de Mendoza. Comparación con la referencia de la Organización Mundial de la Salud / Body mass index, weight, and height percentiles in school-aged children from Mendoza. A comparison with the WHO reference

Introducción. La Organización Mundial de la Salud (OMS) recomienda el uso de tablas de referencia para monitorear el crecimiento y estado nutricional de niños, niñas y adolescentes. El peso corporal, la talla y el índice de masa corporal (IMC) son las variables más utilizadas. El presente trabajo tiene como objetivos estimar los percentiles de peso, talla e IMC de escolares (2009-2011) residentes en el departamento San Rafael (Mendoza) y compararlos con la referencia internacional de la Organización Mundial de la Salud, a fin de establecer su pertinencia para la evaluación del crecimiento y estado nutricional de dicha población. Población y métodos. Se realizó un estudio antropométrico transversal en 3448 escolares de entre 4,00 y 13,49 años de edad. Se utilizó el programa LMS ChartMarker Pro para calcular los valores percentilares de peso/edad, talla/edad e IMC/edad, por sexo y edad, y se compararon con las curvas de la OMS. Además, se calcularon diferencias porcentuales (D%) para estimar las diferencias y su significación estadística mediante prueba de Wilcoxon. Resultados. La población de San Rafael mostró, en varones y mujeres, valores percentilares superiores de peso e IMC (D% ≈7 % y 9 %, respectivamente), y menores de talla (D% ≈0,8 %) que los de la OMS (p <0,05). Conclusión. Las diferencias encontradas alertan sobre el empleo de la referencia OMS en la población escolar de San Rafael, ya que sobreestimaría las prevalencias de sobrepeso, obesidad y desnutrición crónica, y subestimaría la de desnutrición aguda y global. Esta situación resalta la importancia de contar con una referencia local.

Introduction. The World Health Organization (WHO) recommends the use of reference tables to monitor the growth pattern and nutritional status of children and adolescents. Body mass index (BMI), weight, and height are the most commonly used variables. The objective of this study was to estimate the BMI, weight, and height percentiles for school-aged children (2009-2011) living in the department of San Rafael (Mendoza) and compare them to the international World Health Organization reference to establish their relevance for the evaluation of the growth pattern and nutritional status of this population. Population and methods. A cross-sectional anthropometric study was conducted in 3448 school-aged children aged 4.00 to 13.49 years. The LMS ChartMarker Pro software was used to estimate the BMI- for-age, weight-for-age, and height-for-age percentiles, by sex and age, and they were compared with the WHO curves. Besides, percentage differences (%D) were calculated to estimate the differences and their statistical significance using the Wilcoxon test. Results. The population of boys and girls in San Rafael showed higher weight and BMI (%D ≈ 7% and 9%, respectively) percentiles, and lower height (%D ≈ 0.8%) values than WHO reference (p < 0.05). Conclusion. The differences found warn about the use of the WHO reference in the school-aged population of San Rafael since it would overestimate the prevalence of overweight, obesity, and chronic malnutrition and underestimate the prevalence of acute and global malnutrition. This situation highlights the importance of having a local reference resource

Valoraciones sobre el procesamiento de información en investigaciones asociadas a especialidades médicas / Assessments on the processing of information in research associated with medical specialties

RESUMEN El presente trabajo tiene como objetivo valorar las regularidades de los principales problemas que se evidencian en el uso y empleo de la dinámica del procesamiento de la información en investigaciones asociadas a especialidades médicas, a partir de una selección de tesis vinculadas a la especialidad de Medicina General Integral y de otras especialidades médicas defendidas en los últimos 5 años en la Universidad de Ciencias Médicas de Camagüey. Los principales resultados de la revisión documental se centran en deficiencias en la presentación e interpretación de la naturaleza de las relaciones entre las variables del diseño metodológico y las técnicas estadísticas que se utilizan desde el diseño, ejecución y presentación del resultado científico.

SUMMARY The present work aims to assess the regularities of the main problems that are evidenced in the use and employment of the dynamics of information processing in research associated with medical specialties, from a selection of theses linked to the specialty of Comprehensive General Medicine and other medical specialties defended in the last 5 years at the University of Medical Sciences of Camagüey. The main results of the documentary review focus on deficiencies in the presentation and interpretation of the nature of the relationships between the variables of the methodological design and the statistical techniques that are used from the design, execution and presentation of the scientific result.

El Enfoque Bayesiano en las Ciencias de la Salud / The Bayesian Approach in the Health Sciences

En estadística existen dos enfoques básicos, la estadística frecuentista que es la corriente principal y la estadística bayesiana. La mayoría de los principales métodos estadísticos son frecuentistas siendo el enfoque bayesiano más desconocido entre los investigadores. En el presente artículo se exponen los fundamentos lógicos del enfoque bayesiano y su uso mediante un ejemplo de aplicación. En este contexto, más que presentar un debate entre la lógica clásica y la bayesiana, se pretende mostrar de manera introductoria las enormes posibilidades que el enfoque bayesiano puede aportar a la investigación en las Ciencias de la Salud.

In the stadistic field there are two basic approaches, the Frequentist Statistics which is the primary one, and the Bayesian Statistics. The most used statistical methods are the Frequentist methods, being the Bayesian approach the most popular among researchers. In this article, the logical basis of the Bayendian approach and its use are exposed through an application example. In this context, rather than presenting a debate between the classic and the Bayensian logic, it is intended to demonstrate in an introductory method the considerable possibilities how Bayesian approach can contribute to Health and Sciences research.

Summary of Statistical Methods Commonly Used in Clinical Evaluation of / 中国医疗器械杂志

Referring to relevant normative documents, we summarized the commonly used statistical methods in clinical evaluation of

Spatiotemporal analysis of distribution of pest and predator in corn crops

Crop pests have negative impacts on yield. This paper proposes a spatiotemporal geostatistical modeling to compare data of adult Syrphidae fly count and corn leaf aphid Rhopalosiphum maidis (Fitch, 1856) colonies in corn crops. The use of a geostatistical model that allows the space-time variation makes the approach more interesting because it is a more complete model. Multiple regression was used to model the trend component for the variable response adult Syrphidae fly count and corn leaf aphid colonies, with the coordinates serving as covariates and the spatiotemporal variations around the deviation are described by a random spacetime residual field. Finally, the prediction map obtained by kriging may be a biological indicator of possible corn leaf aphid colonies in the corn crop. It was possible to verify that the occurrence of the pest provided a significant increase in adult predators and seminatural habitats may favor populations of natural enemies.

Distribuição espaço-temporal de ocorrências de dengue em Três Corações, Minas Gerais, utilizando processos pontuais / Spatio-temporal distribution of dengue occurrences in Três Corações, Minas Gerais, using point processes

Objetivo: detectar a presença de agrupamentos espaço-temporais dos casos de dengue em Três Corações, Minas Gerais, Brasil, utilizando informações da localização e do tempo de cada ocorrência e a série histórica da precipitação pluviométrica do período de estudo. Métodos: o método Kernel foi utilizado para estimar a intensidade dos casos, enquanto a função K espaço-temporal e o método de varredura foram utilizados para detectar o padrão e identificar agrupamentos, respectivamente. Resultados: a partir dos 2.818 casos observados, verificou-se que a maior parte desses ocorreu no final dos períodos chuvosos. Também foi detectada a presença de agrupamentos de casos, principalmente na Região Central da cidade. Uma razão para a formação de agrupamentos pode ser devido à maior densidade populacional das regiões afetadas. Conclusão: os resultados mostram que indivíduos que moram em regiões densamente povoadas são mais propensos a contrair dengue. Os métodos estatísticos utilizados permitiram caracterizar a distribuição espaço-temporal dos casos de dengue e também podem ser utilizados para analisar outras doenças endêmicas ou pandêmicas, o que pode contribuir para as políticas de prevenção e combate à proliferação dessas doenças.(AU)

Objective: detect the presence of space-time clusters of dengue cases in Três Corações, Minas Gerais, Brazil, using information on the location and time of each occurrence and the historical series of rainfall in the study period. Methods: the Kernel method was used to estimate the intensity of the cases, while the space-time K-function and the scan method were used to detect the pattern and identify clusters, respectively. Results: from the 2,818 observed cases, it was found that most of these occurred in the end of rainy periods. The presence of clusters of cases was also detected, mainly, in the central region of the city. One reason for the formation of clusters may be due to the higher population density of the affected regions. Conclusion: the results show that individuals who live in densely populated regions are more likely to get dengue. The statistical methods used allowed to characterize the spatio-temporal distribution of dengue cases and, they can also be used to analyze other endemic or pandemic diseases, which can contribute to policies to prevent and combat the proliferation of these diseases.(AU)

Spatial-temporal of fire foci in the state of Rio de Janeiro, Brazil / Espaço-temporal de focos de fogo no estado do Rio de Janeiro, Brasil

This study evaluated the space-time variability of fire foci via environmental satellites for the State of Rio de Janeiro (SRJ) based on statistical procedures. The fire foci in the period of 2000 to 2015 were obtained from the BDQueimadas fire database. Descriptive, exploratory, and multivariate statistical analyses were performed in the software environment R i386 version 3.2.5. The north region had 6760 foci (21.11%), the south-central region had 3020 foci (9.43%), the Middle Paraíba had 6,352 foci (19.84%), the Metropolitan areas had 6671 foci (20.83%), and the Green Coast region had 292 foci (0.91%). The cluster analysis identified three homogeneous groups of fire foci (G1, G2, and G3) but did not include the municipality of Campos dos Goytacazes (NA). The G1 group (6.21 ± 0.01 foci, 57.61%) included areas throughout the state and covered the coastal region and lowlands towards the north. The G2 group (6.21 ± 0.01 foci, 34.81%) included the northern, south-central, and coastal shallows regions. The G3 group (6.21 ± 0.01 foci, 9.78%) included the mountain ranges of the state. Environmental characteristics and socioeconomic are crucial in the dynamics of fire foci in Rio de Janeiro.

Este estudo avaliou a variabilidade espaço-temporal de focos de calor via satélites ambientais para o Estado do Rio de Janeiro (SRJ) com base em procedimentos estatísticos. Os focos de calor no período de 2000 a 2015 foram obtidos a partir do banco de dados de focos do BDQueimadas. Análises estatísticas descritivas, exploratórias e multivariadas foram realizadas no ambiente de software R i386 versão 3.2.5. A região Norte tinha 6760 focos (21,11%), a região Centro-Sul tinha 3020 focos (9,43%), o Médio Paraíba tinha 6,352 focos (19,84%), as áreas metropolitanas tinham 6671 focos (20,83%) e a Costa Verde região teve 292 focos (0,91%). A análise de agrupamento identificou três grupos homogêneos de focos de calor (G1, G2 e G3), mas não incluiu o município de Campos dos Goytacazes (NA). Em que se observa no grupo G1 uma forte presença de outliers com valores atípicos, em todos os anos da série temporal, sendo destaque para os anos de 2014 e 2015 que apresentam os maiores números de outliers seguidos dos valores das médias (20.46 e 18.85 focos) acima das medianas (14.00 e 12.50 focos). Comportamentos semelhantes foram observados nos grupos G2 e G3, sendo o grupo G2 com média (81.43 mm e 66.00 focos) e medianas (49.07 e 35.50 focos) com um DP de 27.89 focos de fogo. O grupo G3 com média (314.13 e 361.33 mm) e mediana (204.50 e 76.00 focos) e o maior DP (196,75 focos) em comparação aos demais grupos. Características ambientais e socioeconômicas são cruciais na dinâmica dos focos de calor no Rio de Janeiro.

Non-parametric tests applied to reported cases of dengue in the southeast region of Brazil / Testes não-paramétricos aplicados a casos de dengues reportados na região sudeste do Brasil

Dengue is one of the biggest problems of global public health in developing and underdeveloped countries. Nowadays, researchers in climate changes are concerned about the impact of these changes on human health, particularly with increased this epidemic. Dengue is among the largest public health problems in Brazil and is higher in the months with high temperatures, which is the Aedes aegypti's reproductive period climax. Reported dengue cases via DATASUS from 1994 to 2014 were analyzed. Mann-Kendall (MK), Run and Pettit nonparametric tests; were applied to time series. The run test indicated that the time series is homogenous and persistence free. There is a non-significant trend of increase of a number of reported dengue cases only in Rio de Janeiro. Based on the test, three positive trends were identified in the time series of São Paulo, Minas Gerais and the Espírito Santo States of dengue cases reported in Southeast of Brazil. Pettitt test was able to identify the years classified as El Niño events and that had a significant impact on the increase of dengue cases in the southeastern region of Brazil.

A dengue é um dos maiores problemas de saúde pública global em países em desenvolvimento e subdesenvolvidos. Hoje em dia, os pesquisadores em mudanças climáticas estão preocupados com o impacto dessas mudanças na saúde humana, particularmente com o aumento dessa epidemia. A dengue está entre os maiores problemas de saúde pública no Brasil e é maior nos meses com altas temperaturas, que é o clímax do período reprodutivo do Aedes Aegypti. Foram analisados relatórios de casos de dengue via DATASUS de 1994 a 2014. Testes não paramétricos de Mann-Kendall (MK), Run e Pettit; foram aplicadas em séries temporais. O teste Run indicou que a série temporal é homogênea e sem persistência. Existe uma tendência não significativa de aumento do número de casos de dengue relatados apenas no Rio de Janeiro. Com base no teste, três tendências positivas foram identificadas na série temporal de casos de dengue de São Paulo, Minas Gerais e Espírito Santo relatados no Sudeste do Brasil. O teste de Pettitt foi capaz de identificar os anos classificados como eventos de El Niño e que tiveram um impacto significativo no aumento de casos de dengue na região sudeste do Brasil.

Errores conceptuales de estadística más comunes en publicaciones científicas / Common conceptual statistical mistakes in scientific literature / Equívocos comuns de estatísticas em publicações científicas

Resumen Este trabajo proporciona información actualizada sobre los errores estadísticos que comúnmente se cometen en la literatura científica y como estos podrían ser evitados. El objetivo principal es una revisión de manera conceptual de los errores estadísticos frecuentemente observados, así como defectos y trampas en la ciencia médica y veterinaria para ayudar a los investigadores a producir resultados estadísticamente correctos en sus futuras investigaciones. Al mismo tiempo, esta revisión podría ayudar a que los lectores de revistas científicas identifiquen análisis estadísticos o presentación de datos cuestionables y puedan estimar lo qué los autores habrían concluido si hubieran utilizado métodos estadísticos apropiados.

Abstract This work seeks to provide up-to-date information on commonly made statistical mistakes and statistical reports in scientific papers, and how these can be avoided. The main goal is to comprehensively review frequently observed statistical errors, flaws and pitfalls in medical and veterinary science in order to help researchers to produce statistically correct output in their future reports. At the same time, it can help readers to identify questionable statistical analysis, and estimate what the authors would have concluded when appropriate statistical methods have been used.

Resumo Este trabalho procura fornecer uma atualização sobre os erros estatísticos comumente cometidos na literatura científica e como eles podem ser evitados. O principal objetivo é analisar de uma maneira conceitual defeitos observados frequentemente, erros estatísticos e armadilhas na ciência médica e veterinária para ajudar os pesquisadores a produzir resultados estatisticamente corretos em futuras investigações. Ao mesmo tempo, esta revisão pode ajudar os leitores de revistas científicas a identificar análise estatística ou apresentação de dados questionáveis e estimar o que os autores teria concluído teve eles usaram métodos estatísticos adequados.

Determinación social del proceso salud-enfermedad: una mirada crítica desde la epidemiología del siglo XXI / Social determination of the health-disease process: a critical look from the epidemiology of the 21st century

RESUMEN La llamada determinación social es un concepto central de la Medicina Social Latinoamericana (MSL). Son frecuentes las críticas que la MSL hace a la epidemiología, principalmente por su visión reduccionista y su lejanía a la realidad social. En este ensayo se hace un análisis contrario: la epidemiología del siglo XXI hace una crítica a la MSL, usando como ejemplo el desarrollo disciplinar en Colombia. Se revisa la historia de la epidemiología colombiana indicando que no ha tenido desarrollo suficiente y la MSL tiende a rechazar los métodos cuantitativos con fundamento en la práctica epidemiológica de hace cuatro décadas. Se revisan algunos desarrollos en los métodos cuantitativos usados en epidemiología, indicando que se han superado varias de las limitaciones señaladas por la MSL. Se concluye que la MSL usa la determinación social como parte de su plataforma política de izquierda; sin embargo, los métodos cuantitativos actuales y los desarrollos teóricos en epidemiología del siglo XXI evidencian una superioridad pragmática, útil para solucionar las problemáticas de la salud pública actual.(AU)

ABSTRACT The so-called social determination is a key concept for Latin American Social Medicine (LASM). LASM criticizes epidemiology frequently, mainly because of its reductionist vision and its distance from social reality. This paper makes an opposite analysis, in other words, 21st century epidemiology criticizes LASM, using the disciplinary development in Colombia as an example. The history of Colombian epidemiology is reviewed, noting that it has not had sufficient development and that LASM tends to reject quantitative methods based on the epidemiological practices used four decades ago. Additionally, some developments of the quantitative methods used in epidemiology are reviewed, explaining that many of the limitations indicated by LASM have been overcome. In conclusion, LASM uses social determination as part of its leftist political platform; however, current quantitative methods and the 21st century theoretical developments in epidemiology show a pragmatic superiority, useful for solving current public health issues.(AU)

Comportamento da mortalidade por câncer de mama nos municípios brasileiros e fatores associados / Breast cancer mortality in Brazilian municipalities and associated factors / Mortalidad por cáncer de mama en municipios brasileños y factores asociados

RESUMO Objetivo Analisar o comportamento da mortalidade por câncer de mama nos municípios brasileiros e avaliar a influência de fatores socioeconômicos e demográficos sobre as taxas e mortalidade. Métodos Foram calculadas taxas de mortalidade, padronizadas por faixa etária e corrigidas por causas mal definidas, centradas em 1990, 2000 e 2010. Posteriormente, foram estimados modelos de regressão, com dados em painel, que permitiram verificar o grau de associação entre os fatores de interesse e a taxa de mortalidade pela doença. Resultados Verificou-se uma tendência de crescimento da mortalidade no país. Contudo, os modelos indicaram que a mortalidade poderia ter diminuído (tendência negativa), principalmente no Sudeste e Sul, caso alguns fatores associados à doença (por exemplo, nível de renda, educação, longevidade, taxa de fecundidade, gastos em saúde, infraestrutura, entre outros) tivessem permanecido constantes durante o período considerado. Observou-se que a mortalidade por câncer de mama apresentou associação positiva/significativa com a longevidade e negativa/significativa com o nível de gastos públicos em saúde. A mortalidade foi maior nas regiões Sul e Sudeste, nos municípios com mais de 500 000 habitantes e naqueles onde a população é inferior a 5 000. Conclusões O crescimento da renda per capita, a elevação da expectativa de vida e a diminuição da taxa de fecundidade podem estar associados a elevadas taxas de mortalidade por câncer de mama e a uma tendência de crescimento na mortalidade por esse câncer nos municípios brasileiros.

ABSTRACT Objective To analyze breast cancer mortality trends in Brazilian municipalities and assess the influence of socioeconomic and demographic factors on mortality rates. Methods Age-adjusted mortality rates were calculated for the periods centered in 1990, 2000, and 2010 and corrected for ill-defined causes of death. After that, panel data regression models were developed for analysis of the association between the factors of interest and the mortality rate from breast cancer in Brazilian municipalities. Results A growing trend was detected in breast cancer mortality in Brazil. However, the models showed that the mortality could have decreased (negative trend), especially in the Southeast and South regions, if some associated factors (such as income, education, longevity, fertility rate, health spending, and infrastructure, among others) had remained constant during the study period. Breast cancer mortality was positively/significantly associated with longevity and negatively/significantly associated with public health spending. Mortality was higher in the South and Southeast, in municipalities with more than 500 000 inhabitants and in those with population below 5 000. Conclusions The growth in per capita income, the increase in life expectancy, and the decrease in fertility rates may be associated with high breast cancer mortality and a trend towards increased mortality from this cancer in Brazilian municipalities.

RESUMEN Objetivo Analizar las tendencias de la mortalidad por cáncer de mama en municipios brasileños y evaluar la influencia de factores socioeconómicos y demográficos sobre las tasas de mortalidad. Métodos Se calcularon las tasas de mortalidad, ajustadas por grupo etario y corregidas por causas mal definidas, para los años 1990, 2000 y 2010. Posteriormente, se calcularon modelos de regresión, a partir de datos de panel, que permitieron verificar el grado de asociación entre distintos factores de interés y la tasa de mortalidad por esta enfermedad. Resultados Se verificó que había una tendencia al aumento de la mortalidad en el país. Sin embargo, los modelos indicaron que la mortalidad podría haber disminuido (tendencia negativa), principalmente en el sudeste y el sur, si algunos factores asociados (por ejemplo, nivel de ingresos, educación, longevidad, tasa de fecundidad, gastos en salud, infraestructura, entre otros) hubieran permanecido constantes durante el período en estudio. Se observó que la mortalidad por cáncer de mama presentó una asociación positiva y significativa con la longevidad, y negativa y significativa con el nivel del gasto público en salud. La mortalidad fue mayor en las zonas sur y sudeste, en los municipios con más de 500 000 habitantes y en aquellos cuya población es inferior a 5000. Conclusiones El aumento de los ingresos per cápita, el incremento de la esperanza de vida y la disminución de la tasa de fecundidad pueden estar asociados a tasas altas de mortalidad por cáncer de mama y a una tendencia al aumento de dicha mortalidad en los municipios brasileños.

Key Questions and Thoughts of Scale Development of TCM Syndrome / 中国中医药信息杂志

Targeting the key questions in the scale development process of TCM syndrome, such as the definition of the concept, the construction of the theoretical framework, the quantitative classification of the items, the rational use of the statistical methods and so on, this article put forward that on the basis of carefully distinguishing the three concepts of syndrome diagnosis, syndrome evaluation and disease diagnosis, and based on TCM dialectical thinking and mathematical validation to build theoretical framework. A scientific and reasonable quantitative classification method was established based on the reliability and validity as indexes. Non-linear intelligent mathematical statistics and symptomatic index groups were used to analyze the ideas and methods of data mining, with a purpose to improve and perfect the methodology of the development of syndromes scale and to improve the establishment and application of the syndrome scale.

Sistema de tareas docentes interdisciplinarias para contribuir al aprendizaje de los métodos estadísticos / System of interdisciplinary educational tasks to contribute to the learning of the statistical methods

Fundamento: El desempeño profesional de excelencia requiere, en gran medida, la práctica de la medicina basada en evidencias, así como egresar desde la enseñanza superior, personal de salud capaz de utilizar la estadística en la investigación científica como herramienta que permita elevar la calidad del proceso. Objetivo: Proponer un sistema de tareas docentes interdisciplinarias para contribuir al aprendizaje de métodos estadísticos en las investigaciones, actuando como consumidor y reproductor de información biomédica. Metodología: Investigación pedagógica realizada en la Filial Universitaria de Cabaiguán. Se emplearon los métodos histórico-lógico, el análisis-síntesis, sistémico, el criterio de expertos, hipotético-deductivo e inductivo-deductivo. Resultados: Un sistema de tareas para la búsqueda de información y solución a problemas que se presentan en la etapa estudiantil y profesional, adquisición de conocimientos y comparación de resultados obtenidos en sus investigaciones con los de otros autores. Conclusiones: El sistema de tareas docentes interdisciplinarias propuesto, además de estar fundamentado teóricamente, tiene potencialidades para incentivar la motivación del estudiante y resulta factible su aplicación en el contexto formativo actual.

Background: The professional acting of excellence requires, in great measure, the practice of the medicine based on evidences, as well as graduate from the higher education, personal of health able to use the statistic in the scientific investigation as a tool that allows to elevate the quality of the proces. Objective: To propose a system of interdisciplinary educational tasks to contribute to the learning of statistical methods in the investigations, acting as consumer and reproducer of biomedical informatio. Methodology: Pedagogic investigation carried out in the University Branch of Cabaiguán. The historical-logical, the analysis-synthesis, systemic, the approach of experts, hypothetical-deductive and inductive-deductive methods were used. Results: A system of tasks for the search of information and solution to problems that are presented in the student and professional stage, acquisition of knowledge and comparison of results obtained in their investigations with those of other authors. Conclusions: The proposed system of interdisciplinary educational tasks, besides being based theoretically, has potentialities to incentive the student's motivation and it is feasible its application in the current formative context.

Descripción del Crecimiento de Ovinos Santa Inés x Criollo Manejados en Pastoreo Extensivo en Dos Poblaciones de Córdoba, Colombia / Description of Growth in Sheep Santa Ines x Creole in Extensive Grazing in Two Populations from Cordoba, Colombia

Con el objetivo de evaluar el modelo que mejor describe el crecimiento de ovinos Santa Inés x Criollo en dos poblaciones ovinas del Departamento de Córdoba, Colombia y determinar el efecto de sexo y finca sobre los parámetros estimados, se evaluaron los modelos de: Brody, Logístico, Gompertz y Von Bertalanffy. Además, se estimó el porcentaje de madurez a los 4 y 6 meses y la edad al 75 y 95% de madurez para el modelo que mejor describió la curva de crecimiento. Para ello, fueron utilizados registros de pesos de 77 ovinos nacidos entre los meses de noviembre de 2013 y abril de 2014. Los parámetros fueron estimados usando el procedimiento NLIN de SAS. Para verificar cuál curva sería la adecuada para describir el crecimiento de las poblaciones estudiadas, se consideró el criterio de información Aikaike, el criterio de información Bayesiano, el coeficiente de determinación y el porcentaje de curvas convergentes. El modelo que presentó mejor ajuste fue el Von Bertalanffy. Para este modelo el efecto sexo no fue significativo (P>0,05) para ninguno de los parámetros estimados. El efecto finca fue significativo (P≤0,05) para todos los parámetros estimados. Los estimados para β0, β1 y β2 fueron 41,21; 0,5896 y 0,0075, respectivamente. El porcentaje de madurez a los cuatro meses fue de 42,25% y a los seis meses de 56,12%; la edad al 75 y 95% de madurez fue de 310 y 589 d, respectivamente. De acuerdo a los valores estimados, para porcentaje de madurez y edad a la madurez, en las poblaciones ovinas estudiadas, se deben mejorar las condiciones de manejo nutricional y alimenticio de los animales, para que éstos logren la madurez a menor edad.

With the objective to verify which was the model that best describes the growth of sheep Santa Ines x Creole in two sheep populations in the department of Cordoba, Colombia, and determine the effect of sex and farm on the estimated parameters, models of Brody, Logistic models Gompertz and Von Bertalanffy were evaluated. In addition, the percentage of maturity at 4 to 6 months, and age at 75 and 95% maturity was estimated for the model that best described the growth curve. Weighing 77 sheep born between the months of November 2013 and April 2014 were used. The parameters were estimated using the procedure NLIN of SAS. To verify that curve would be adequate to describe the growth of the populations studied Aikaike Information Criterion, the Bayesian Information Criterion, the Coefficient of Determination and Percentage of Curves Converged were considered. Von Bertalanffy model was presented better fit. For this model, sex effect was not significant for any of the estimated parameters. The farm effect was significant for all the estimated parameters. Von Bertalanffy model showed a better adjustment. For this model, sex effect was not significant (P>0.05) for any of the estimated parameters. The farm effect was highly significant (P≤0.05) for all the estimated parameters. The estimates for β0, β1 and β2 were 41.21, 0.5896 and 0.0075, respectively. The percentage of maturity at four months was 42.25% and 56.12% at six; age at 75% and 95% of maturity were 310 and 589 d, respectively. According to the estimated percentage of maturity and age at maturity, in sheep populations studied should improve the nutritional management and food of the animals, in order that they achieve maturity at a younger age.

Desempenho no Enade de bolsistas ProUni: Modelagem de Equações Estruturais / ProUni Scholar students performance in Enade: Structural Equations Modeling

Resumo Esse estudo objetivou investigar o desempenho no Enade de estudantes bolsistas do Programa Universidade para Todos - ProUni da própria instituição e de estudantes com outros tipos de bolsas e, ainda investigar, por meio de Modelos de Equações Estruturais, se este desempenho se mantém para estudantes sob a condição de ingressantes e concluintes. Utilizou-se um banco de dados contendo os resultados de 401.117 estudantes que realizaram o exame do Enade em 2006, composto pelas provas de Formação Geral e de Conhecimento Específico. O mesmo modelo de equações estruturais foi utilizado para analisar os dados de estudantes ingressantes e concluintes. Os resultados obtidos indicaram que o modelo de mensuração dos estudantes bolsistas com relação às notas do Enade apresenta um ajuste razoavelmente bom e permite afirmar que o desempenho do estudante durante a graduação é inferior ao do momento de seu ingresso no Ensino Superior.(AU)

Abstract This study aimed to investigate the performance in the National Students Exam-Enade of students with scholarships ProUni ("University for all" Programme), with grants of the education institutions themselves and students with other types of scholarships, and also to investigate, through the Structural Equation Modeling, whether this performance is maintained under the conditions of freshmen and seniors. We used a database containing the results of 401,117 students who took the Enade exam in 2006, which is composed both of the General Formation and the Specific Knowledge tests. The same structural equation model was used to analyse the database of freshmen and seniors students. The obtained results indicated that the measurement model of the scholar students concerning the Enade grades provides a reasonably good fit and allows us to say that the student´s performance through graduation is poorer than the moment of their admission to College.(AU)

Test of association: which one is the most appropriate for my study?

AbstractBACKGROUND:Hypothesis tests are statistical tools widely used for assessing whether or not there is an association between two or more variables. These tests provide a probability of the type 1 error (p-value), which is used to accept or reject the null study hypothesis.OBJECTIVE:To provide a practical guide to help researchers carefully select the most appropriate procedure to answer the research question. We discuss the logic of hypothesis testing and present the prerequisites of each procedure based on practical examples.

Review of research designs and statistical methods employed in dental postgraduate dissertations.

Context: There is a need to evaluate the quality of postgraduate dissertations of dentistry submitted to university in the light of the international standards of reporting. Aims: We conducted the review with an objective to document the use of sampling methods, measurement standardization, blinding, methods to eliminate bias, appropriate use of statistical tests, appropriate use of data presentation in postgraduate dental research and suggest and recommend modifications. Settings and Design: The public access database of the dissertations from Rajiv Gandhi University of Health Sciences was reviewed. Subjects and Methods: Three hundred and thirty‑three eligible dissertations underwent preliminary evaluation followed by detailed evaluation of 10% of randomly selected dissertations. The dissertations were assessed based on international reporting guidelines such as strengthening the reporting of observational studies in epidemiology (STROBE), consolidated standards of reporting trials (CONSORT), and other scholarly resources. Statistical Analysis Used: The data were compiled using MS Excel and SPSS 10.0. Numbers and percentages were used for describing the data. Results: The “in vitro” studies were the most common type of research (39%), followed by observational (32%) and experimental studies (29%). The disciplines conservative dentistry (92%) and prosthodontics (75%) reported high numbers of in vitro research. Disciplines oral surgery (80%) and periodontics (67%) had conducted experimental studies as a major share of their research. Lacunae in the studies included observational studies not following random sampling (70%), experimental studies not following random allocation (75%), not mentioning about blinding, confounding variables and calibrations in measurements, misrepresenting the data by inappropriate data presentation, errors in reporting probability values and not reporting confidence intervals. Few studies showed grossly inappropriate choice of statistical tests and many studies needed additional tests. Conclusions: Overall observations indicated the need to comply with standard guidelines of reporting research.

Validation of the Cognitive Structure of an Arithmetic Test with the Least Squares Distance Model (LSDM) / Validación de la estructura cognitiva de una prueba aritmética con el Modelo de Distancia Mínima de Cuadrados (LSDM)

The aim of the present paper is to collect evidence about validity of the cognitive structure proposed to solve the items of an arithmetic test using an cognitive diagnosis model (based on the Item Response Theory) called Least Squares Distance Model (LSDM). The test was applied to a sample of 382 students of 7th grade from five public high schools in Bogotá-Colombia. With this data the objective was addressed in three ways: first, the analysis of two statistical validity indices; second by a cross -validation of the LSDM results on attribute difficulties using other cognitive model (LLTM), and third, by comparing the LSDM results with the observed scores on individual attributes. The logical behavior of the probability curves for the five attributes under study provides important evidence for their overall validity. Additional specific evidences of validity are also presented in the results.

El objetivo del presente trabajo ha sido reunir evidencias sobre la validez de la estructura cognitiva propuesta para resolver los ítems de un test de aritmética, mediante la aplicación de un modelo de diagnóstico cognitivo basado en la Teoría de Respuesta al Item llamado Modelo de las Distancias Mínimo Cuadráticas (LSDM, por sus siglas en inglés). El test se aplicó a una muestra de 382 estudiantes de séptimo grado en cinco colegios públicos en Bogotá-Colombia. Usando estos datos el objetivo se abordó de tres maneras: en primer lugar se analizaron dos índices estadísticos de validez, en segundo lugar, se realizó una validación cruzada de los resultados del LSDM sobre las dificultades de atributos utilizando otro modelo cognitivo (LLTM) y en tercer lugar, se compararon los resultados del modelo con las puntuaciones observadas en atributos individuales. El comportamiento lógico de las curvas de probabilidad para los cinco atributos estudiados proporciona importante evidencia para su validez general. En los resultados se presentan también otras evidencias concretas de validez de la estructura propuesta.

Data dimensionality reduction for hospital efficiency measurement / 中华医院管理杂志

A comparison was made for the correlation and application scope of the statistical methods commonly used by hospitals for their efficiency measurement.Hospital data processed with PCA (principal component analysis)for dimension reduction were used in a correlation analysis for the results of ratio analysis (RA),stochastic frontier analysis(SFA)and data envelopment analysis(DEA).The authors hold that the RA can expediently display the order of hospital efficiency,the SFA demands a stricter premise yet presents more stable results,while the DEA boasts greater relative advantages and thus suitable for processing hospital efficiency measurement tasks of multi-input and multi-output indexes.

Optimization of zofimarin production by an endophytic fungus, Xylaria sp. Acra L38

To optimize the medium for high zofimarin production, sucrose maltose, glucose, tryptone and peptone were used in an orthogonal array design experiment, where the highest value of zofimarin produced was 25.6 µg/mL. This value was about 3 times higher than that obtained with Czapek yeast extract (CzYE) culture medium. A study with Plackett-Burman design showed that sucrose, maltose, glucose and NaNO3 were significant factors in zofimarin production. Further studies using central composite design (CCD) showed the significance of glucose and the interactions of these critical components affecting zofimarin production. Multiple regression analysis of the data yielded a poor fit as shown by the mismatch of the model with these variable factors. When a polynomial equation was applied, the maximum zofimarin production was predicted to be 201.9 µg/mL. Experimental verification yielded a much lower amount of zofimarin, at around 70 µg/mL. Reconsideration of the CCD data and repetition of some runs with high zofimarin production resulted in reproducible zofimarin yield at 79.7 µ/mL. Even though the amount was lower than the predicted value, the medium optimization study was considered to be quite successful as the yield increased to around 8 times that obtained with the original CzYE culture medium.