Carcinoma de mama triple negativo. Estudio anatomo-estadístico / Triple- negative breast cancer. An anatomical and statistical study

Introducción: El carcinoma de mama triple negativo se asocia a un comportamiento biológico más agresivo y de desfavorable pronóstico. Objetivo: Determinar la incidencia del subtipo molecular triple negativo en carcinomas mamarios y su relación con otras variables clínico-patológicas de valor pronóstico. Método: Se realizó un estudio descriptivo y retrospectivo, en el Hospital Universitario Docente «Celestino Hernández Robau» de Villa Clara, en el período comprendido de enero de 2017 a junio de 2019, con el fin de determinar la incidencia de los tumores triples negativos y su relación con las variables edad, talla tumoral, tipo y grado histológicos e índice de proliferación. Resultados: Se determinó la incidencia del subtipo molecular triple negativo en carcinomas mamarios y su relación con las formas histológicas moderada y poco diferenciadas. Conclusiones: El subtipo molecular triple negativo en carcinomas mamarios está asociado con frecuencia a: la edad posmenopáusica, el tipo histológico ductal, el grado histológico alto, altos índices de Ki-67 y talla tumoral mayor de 2 cm.

Introduction: triple-negative breast cancer has a more aggressive biological behaviour and is associated with an unfavourable prognosis. Objective: to determine the incidence of triple- negative breast cancer molecular subtypes and its relationship with other clinical and pathological variables of prognostic value. Methods: a descriptive and retrospective study was carried out at "Celestino Hernández Robau" University Teaching Hospital from Villa Clara between January 2017 and June 2019 in order to determine the incidence of triple- negative tumors and its relationship with the variables: age, tumor size, histological type and grade as well as proliferative index. Results: the incidence of triple- negative breast cancer molecular subtype and its relationship with moderate and poorly differentiated histological forms were determined. Conclusions: triple- negative breast cancer molecular subtype is frequently associated with postmenopausal age, ductal histological type, high histological grade, high Ki-67 indices and tumor size greater than 2 cm.

Tamanho do efeito em estudos observacionais na área de Saúde Bucal Coletiva: importância, cálculo e interpretação / Size effect in observational studies in Public Oral Health: importance, calculation and interpretation

Resumo O objetivo deste estudo foi analisar a literatura científica da área de saúde bucal coletiva quanto ao cálculo, apresentação e discussão do tamanho do efeito em estudos observacionais. A literatura cientifica na área (2015 a 2019) foi analisada quanto: a) informações gerais (periódico e diretrizes aos autores, número de variáveis e desfechos), b) objetivo e coerência com o cálculo amostral apresentado; c) tamanho do efeito (apresentação, medida utilizada e coerência com a discussão dos dados e conclusão). Foram analisados 123 artigos, de 66 periódicos. A maioria dos artigos avaliados apresenta um único desfecho (74%) e não menciona a realização de cálculo amostral (69,9%). Dentre os que realizaram, para 70,3% havia coerência entre o cálculo amostral utilizado e o objetivo. Apenas 3,3% dos artigos mencionam o termo tamanho do efeito e 24,4% não o consideram na discussão dos resultados, apesar de terem calculado. A regressão logística foi a metodologia estatística mais utilizada (98,4%) e o Odds Ratio a medida de tamanho do efeito mais utilizada (94,3%), embora não tenha sido citada e discutida como uma medida de tamanho do efeito na maioria dos estudos (96,7%). Os pesquisadores, em sua maioria, restringiram a discussão dos resultados apenas à significância estatística encontrada nas associações testadas.

Abstract The objective of this study was to analyze the scientific literature in public oral health regarding calculation, presentation, and discussion of the effect size in observational studies. The scientific literature (2015 to 2019) was analyzed regarding: a) general information (journal and guidelines to authors, number of variables and outcomes), b) objective and consistency with sample calculation presentation; c) effect size (presentation, measure used and consistency with data discussion and conclusion). A total of 123 articles from 66 journals were analyzed. Most articles analyzed presented a single outcome (74%) and did not mention sample size calculation (69.9%). Among those who did, 70.3% showed consistency between sample calculation used and the objective. Only 3.3% of articles mentioned the term effect size and 24.4% did not consider that in the discussion of results, despite showing effect size calculation. Logistic regression was the most commonly used statistical methodology (98.4%) and Odds Ratio was the most commonly used effect size measure (94.3%), although it was not cited and discussed as an effect size measure in most studies (96.7%). It could be concluded that most researchers restrict the discussion of their results only to the statistical significance found in associations under study.

Empleo de células madre mononucleares en el tratamiento de osteoartritis en rodilla: caso de estudio en Cuba / Using Mononuclear Stem Cells for Osteoarthritis-Knee Treatments: A Case Study in Cuba / Uso de células-tronco mononucleares no tratamento da osteoartrite de joelho: estudo de caso em Cuba

Resumen Introducción: el desarrollo alcanzado en la medicina regenerativa posibilita el tratamiento de enfer medades incurables o que tienen una respuesta reducida a las terapéuticas actuales, así como la dis minución del consumo de medicamentos, en algunos casos. En Cuba, las especialidades de angiología y de ortopedia y traumatología son las que más han aplicado esta terapia. En el artículo se interpretan estadísticamente los resultados de la comparación, mediante STATGRAPHICS® Centurion XVI, de las varia bles controladas en dos tratamientos de osteoartritis en rodilla, uno empleando células madre mononucleares obtenidas de la sangre periférica y otro con la terapia convencional, para fundamentar la superioridad del nuevo tratamiento. Presentación del caso: se trataron 100 pacientes adultos atendidos en el Departamento de Ortopedia del Instituto de Hematología e Inmunología por osteoartrosis de rodilla, divididos en dos grupos. El grupo A (control) recibió el tratamiento convencional de infiltración con acetato de triamcinolona en la articulación afectada. El grupo B (estudio) recibió la implantación del concentrado de células mononucleares adultas hematopoyéticas por vía percutánea. Conclusión: se analizaron cada una de sus variables y se pudo comprobar que la mayoría de los datos recopilados no cumplía con una distribución normal, por lo que las siguientes pruebas se ejecutaron tomando como referencia la mediana de cada muestra. Se comparó entre la evaluación del dolor a la actividad y el consumo de medicamentos de cada uno de los grupos de tratamiento. Se evidenció la mejor respuesta de los pacientes para el tratamiento con células madre y una disminución en el consumo de fármacos.

Abstract Introduction: The development achieved in regenerative medicine has allowed the treatment of incurable diseases or those with a reduced response to current therapies, as well as cases with decreased consump tion of medicines. In Cuba, angiology, orthopedic, and traumatology specialists use this therapy the most. In this paper, we have presented the statistical analysis using the STATGRAPHICS® Centurion XVI for controlled variables in two osteoarthritis-knee treatments, one using mononuclear stem cells obtained from the peripheral blood and the other with a conventional therapy so as to demonstrate the superiority of the new treatment regime. Case report: A total of 100 adult patients treated in the Orthopedic Department at the Hematology and Immunology Institute for osteoarthritis-knee pains were studied. Group A (control) received the conventional treatment with triamcinolone acetate infiltration in the affected knee. Group B received the percutaneous implantation of the hematopoietic adult mononuclear cell concentrate. Conclusion: The analysis of each of the variables was performed to verify that most of the collected data did not comply with a normal distribution; hence, the following tests were performed taking the median of each sample as a reference. Comparisons were made between the evaluation of pain to the activity, as well as the consumption of drugs from each of the treatment groups. The best response of the patients was indicated for treatments with stem cells and a decrease in the consumption of drugs.

Resumo Introdução: o desenvolvimento alcançado na medicina regenerativa possibilita o tratamento de doenças incuráveis ou que têm uma resposta reduzida frente às terapias atuais, bem como a redução do consumo de medicamentos, em alguns casos. Em Cuba, as especialidades de angiologia e ortopedia e traumato logia são as que mais têm aplicado esta terapia. O estudo interpreta estatisticamente os resultados da comparação, por meio do STATGRAPHICS® Centurion XVI, das variáveis controladas em dois tratamentos de osteoartrite de joelho, sendo um utilizando células-tronco mononucleares obtidas de sangue periférico e outro com terapia convencional, com o objetivo de comprovar a superioridade do novo tratamento. Apresentação do caso: foram tratados 100 pacientes adultos atendidos no Departamento de Ortopedia do Instituto de Hematologia e Imunologia para osteoartrite de joelho, divididos em dois grupos. O grupo A (controle) recebeu tratamento convencional de infiltração com acetato de triancinolona na articulação afetada. O grupo B (estudo) recebeu implantação percutânea de concentrado de células mononucleares hematopoiéticas adultas. Conclusão: a análise de cada uma de suas variáveis foi realizada e constatou-se que a maioria dos dados coletados não obedecia a uma distribuição normal, de modo que os seguintes testes foram realizados tomando-se como referência a mediana de cada amostra. Foram feitas compara ções entre a avaliação da dor à atividade, bem como o consumo de medicamentos em cada um dos grupos de tratamento. Evidenciou-se uma melhor resposta dos pacientes ao tratamento com células-tronco e diminuição do consumo de medicamentos.

Release report of the Eighth National Survey on Student Physical Fitness and Health / 中国学校卫生

Abstract@#In 2019, the Ministry of Education and other departments launched the Eighth National Survey on Student Physical Fitness and Health, in accordance with the National Student Physique and Health Survey System approved by the State Council in 1987. The general improvement student physical and health in China has been made, and the primary factors enhaneing students physical fitness and health have been put forward. In terms of the findings in this survey, the following relevant arrangements are proposed: comprehensively strengthening and improving school physical education, implementing school health and health education policy requirements, continuing comprehensive prevention and control of myopia among children and adolescents, and implementing the national plan for the construction of healthy schools.

Mulheres que fizeram aborto no Município do Rio de Janeiro, Brasil: aplicação de um modelo hierárquico bayesiano / Mujeres que abortaron en el Municipio de Río de Janeiro, Brasil: aplicación de un modelo jerárquico bayesiano / Women who have undergone abortion in the city of Rio de Janeiro, Brazil: application of a Bayesian hierarchical model

Resumo: Estimativas de mulheres que fizeram aborto provocado em localidades cujas leis são restritivas ainda são escassas na literatura científica, e a não coincidência de estimativas oriundas dos métodos hoje em uso clama pela aplicação de métodos inovadores, como novos métodos indiretos. Tal necessidade é especialmente aguda nas áreas mais densamente povoadas, como as capitais brasileiras, dada a magnitude do fenômeno e os danos e riscos daí decorrentes. O artigo objetiva estimar o número de mulheres que fez aborto provocado no Município do Rio de Janeiro, Brasil, em 2011, por meio de um modelo hierárquico bayesiano. Ele foi aplicado aos dados de um inquérito domiciliar que subsidiou a utilização do método network scale-up, no Município do Rio de Janeiro, um modelo hierárquico bayesiano utilizando as informações indiretas baseadas na rede de contatos dos participantes selecionados de forma aleatória da população. Das 1.758.145 mulheres de 15-49 anos residentes no Município do Rio de Janeiro (13.025; ICr95%: 10.635; 15.748) mulheres fizeram aborto provocado em 2011, resultando numa incidência acumulada média de 7,41 (ICr95%: 6,05; 8,96) para cada 1.000 mulheres de 15-49 anos. O estudo de autovalidação do modelo permitiu identificar padrões de subestimação em subpopulações estigmatizadas com baixa visibilidade social, como mulheres fizeram aborto provocado. O abortamento provocado é uma prática recorrente entre as mulheres no Município do Rio de Janeiro. Novos métodos de estimação indireta podem contribuir para a apreensão mais precisa do evento, considerando o contexto de ilegalidade, e contribuir para formulação de políticas de saúde.

Resumen: Las estimaciones de mujeres que tuvieron un aborto provocado en localidades cuyas leyes son restrictivas todavía son escasas en la literatura científica, y la no coincidencia de las estimaciones procedentes de los métodos hoy en uso reclama urgentemente la aplicación de métodos innovadores, como los nuevos métodos indirectos. Tal necesidad es especialmente acuciante en las áreas más densamente pobladas, como las capitales brasileñas, dada la magnitud del fenómeno y los daños y riesgos derivados de allí. El artículo tiene como objetivo estimar el número de mujeres que realizaron un aborto provocado en el Municipio de Río de Janeiro, Brasil, en 2011, a partir de un modelo jerárquico bayesiano. Este se aplicó a los datos de una encuesta domiciliaria que fomentó la utilización del método network scale-up, en el Municipio de Río de Janeiro, un modelo jerárquico bayesiano utilizando información indirecta, basada en la red de contactos de los participantes seleccionados de forma aleatoria en la población. De las 1.758.145 mujeres de 15-49 años, residentes en el Municipio de Río de Janeiro, 13.025 (ICr95%: 10.635; 15.748) mujeres tuvieron un aborto provocado en 2011, resultando en una incidencia acumulada media de 7,41 (ICr95%: 6,05; 8,96) para cada 1.000 mujeres de 15-49 años. El estudio de autovalidación del modelo permitió identificar patrones de subestimación en subpoblaciones estigmatizadas con baja visibilidad social, como las mujeres que tuvieron un aborto provocado. El aborto provocado es una práctica recurrente entre mujeres en el municipio de Río de Janeiro. Nuevos métodos de estimación indirecta pueden contribuir a la aprehensión más precisa de este evento, considerando el contexto de ilegalidad, y contribuir a la formulación de políticas de salud.

Abstract: Estimates of number of women who have undergone induced abortion in jurisdictions with restrictive abortion laws are still scarce in the scientific literature, and the disparate estimates from currently used methods call for the application of innovative estimation techniques such as new indirect methods. This need is especially acute in more densely populated areas, such as Brazil's state capitals, given the magnitude of unsafe abortions and the resulting risks and harms. The article aims to estimate the number of women who had induced abortions in the city of Rio de Janeiro in 2011, based on a Bayesian hierarchical model. The model was applied to data from a household survey that supported the use of the network scale-up method in the city of Rio de Janeiro, a Bayesian hierarchical model using indirect information based on the contact networks of randomly selected participants from the general population. Among the 1,758,145 women 15-49 years of age living in the city of Rio de Janeiro, 13,025 women (95%CrI: 10,635; 15,748) had induced abortions in 2011, resulting in a mean cumulative incidence of 7.41 (95%CrI: 6.05; 8.96) for every 1,000 women 15-49 years of age. The model's self-validation process identified patterns of underestimation in stigmatized subpopulations with low social visibility, such as women who have undergone induced abortion. Induced abortion is a common practice among women in the city of Rio de Janeiro. New indirect estimation methods can contribute to more precise measurement of this event, considering the context of illegality, and thereby contribute to appropriate health policies.

Multicollinearity and misleading statistical results / 대한마취과학회지

Multicollinearity represents a high degree of linear intercorrelation between explanatory variables in a multiple regression model and leads to incorrect results of regression analyses. Diagnostic tools of multicollinearity include the variance inflation factor (VIF), condition index and condition number, and variance decomposition proportion (VDP). The multicollinearity can be expressed by the coefficient of determination (R(h)²) of a multiple regression model with one explanatory variable (X(h)) as the model’s response variable and the others (X(i) [i≠h] as its explanatory variables. The variance (σ(h)²) of the regression coefficients constituting the final regression model are proportional to the VIF(1/1−R(h)²). Hence, an increase in R(h)² (strong multicollinearity) increases σ(h)². The larger σ(h)² produces unreliable probability values and confidence intervals of the regression coefficients. The square root of the ratio of the maximum eigenvalue to each eigenvalue from the correlation matrix of standardized explanatory variables is referred to as the condition index. The condition number is the maximum condition index. Multicollinearity is present when the VIF is higher than 5 to 10 or the condition indices are higher than 10 to 30. However, they cannot indicate multicollinear explanatory variables. VDPs obtained from the eigenvectors can identify the multicollinear variables by showing the extent of the inflation of σ(h)² according to each condition index. When two or more VDPs, which correspond to a common condition index higher than 10 to 30, are higher than 0.8 to 0.9, their associated explanatory variables are multicollinear. Excluding multicollinear explanatory variables leads to statistically stable multiple regression models.

A Statistical Analysis on Forensic Autopsies Performed in Korea in 2017 / 대한법의학회지

Statistical analysis was performed on national forensic autopsy data collected in the Republic of Korea, with the exception of Ulsan, during 2017. A total of 8,777 cases were categorized based on the region; information was provided by the Police Agency and the Coast Guard regarding sex, age, manner of death, and cause of death. Analysis of the manner of death revealed that 3,971 cases (45.2%) were unnatural deaths, 3,679 cases (41.9%) were natural deaths, and 1,127 cases (12.8%) were unknown deaths. Among the unnatural deaths, the majority of the cases (1,740 cases, 43.8%) were accidents, 1,316 cases (33.1%) were suicide, 385 cases (9.7%) were homicide, and 530 cases (13.3%) were undetermined deaths. Among the unnatural deaths, the majority of the cases (1,575 cases, 39.7%) were trauma, followed by 793 cases (20.0%) of poisoning and 689 cases (17.4%) of asphyxia. Falling down was the major cause of death by trauma (737 cases, 46.8%). As a result of the classification of asphyxia based on previous study, strangulation was the major cause, with 538 cases (78.1%). Among the natural deaths, heart disease was the major cause (1,790 cases, 48.7%), followed by vascular disease (697 cases, 18.9%).

Study for Lists of Forensic Autopsy Request: Quantitative Analysis about Documents Relating to Autopsy Request / 대한법의학회지

In the Republic of Korea, relevant documents are submitted to forensic doctors or agencies when courts grant confiscation warrants for autopsy. If the essential data on unusual death are not submitted at the time of the autopsy, it may be difficult to properly understand the situation relating to an unusual death prior to the autopsy, thus reducing the accuracy of the autopsy. As many as 6,133 out of 6,610 autopsy data (92.8%) in the Republic of Korea in 2015 were analyzed. Most autopsy appraisal requests (99.8%) were submitted. Unusual death occurrence reports (86.0%) and command recommendations of unusual death (70.3%) were submitted in many cases. However, prosecutor commands on unusual death were submitted only in 27.8% cases, and confiscation warrants were not submitted in 7.4% cases. As for postmortem inspection and death scene investigation reports, 29.3% and 34.1% cases were submitted, respectively. In addition to the above two documents, death certificates and records of statement of a relative had significant regional variations (0.3%–80.1%, 3.1%–64.7%, 27.8%–81.3%, and 40.8%–96.8%, respectively). For postmortem inspection and death scene photos, 2.7% and 3.2% were submitted in black-and-white photographs, respectively. The authors propose a list of forensic autopsy requests including autopsy appraisal requests, unusual death occurrence reports, command recommendations of unusual deaths, prosecutor commands on unusual death, and confiscation warrants unconditionally, as an essential document reflecting the progress of investigations. We suggest that postmortem inspection reports and photos, death scene investigation reports and photos, and death certificates should be included as part of postmortem investigation data.

A Statistical Analysis on Forensic Autopsies Performed in Korea in 2016 / 대한법의학회지

A statistical analysis was performed on national forensic autopsy data collected in the Republic of Korea during 2016 to overcome regional limitations and limitations from the number of unusual deaths as reported in the literature over the previous year. A total of 8,335 cases were categorized based on the region, based on requests by the Police Agency and the Coast Guard, gender, age, manner of death, and cause of death. Analysis of the manner of death revealed that 4,028 cases (48.3%) were of unnatural death, 3,447 cases (41.4%) were of natural death, and 860 cases (10.3%) were of unknown death. Among the unnatural deaths, the majority of the manner of deaths (1,584 cases, 39.3%) was accidents, 1,378 cases (34.2%) were suicides, 428 cases (10.6%) were homicides, and 638 cases (15.8%) were undetermined deaths. Among the unnatural deaths, the majority of the cause of deaths (1,518 cases, 37.7%) was due to trauma, followed by 827 cases (20.5%) of poisoning and 732 cases (18.2%) of asphyxia. Falling was the major cause of death by trauma (668 cases, 44.0%). Based on a previous study about asphyxia, strangulation was the major cause, with 569 cases (77.7%). Among the natural deaths, heart disease was the major cause (1,727 cases, 50.1%), followed by vascular disease (587 cases, 17.0%).

Texture Analysis of Torn Rotator Cuff on Preoperative Magnetic Resonance Arthrography as a Predictor of Postoperative Tendon Status

OBJECTIVE: To evaluate texture data of the torn supraspinatus tendon (SST) on preoperative T2-weighted magnetic resonance arthrography (MRA) using the gray-level co-occurrence matrix (GLCM) for prediction of post-operative tendon state. MATERIALS AND METHODS: Fifty patients who underwent arthroscopic rotator cuff repair for full-thickness tears of the SST were included in this retrospective study. Based on 1-year follow-up, magnetic resonance imaging showed that 30 patients had intact SSTs, and 20 had rotator cuff retears. Using GLCM, two radiologists measured independantly the highest signal intensity area of the distal end of the torn SST on preoperative T2-weighted MRA, which were compared between two groups.The relationships with other well-known prognostic factors, including age, tear size (anteroposterior dimension), retraction size (mediolateral tear length), grade of fatty degeneration of the SST and infraspinatus tendon, and arthroscopic fixation technique (single or double row), also were evaluated. RESULTS: Of all the GLCM features, the retear group showed significantly higher entropy (p < 0.001 and p = 0.001), variance (p = 0.030 and 0.011), and contrast (p = 0.033 and 0.012), but lower angular second moment (p < 0.001 and p = 0.002) and inverse difference moment (p = 0.027 and 0.027), as well as larger tear size (p = 0.001) and retraction size (p = 0.002) than the intact group. Retraction size (odds ratio [OR] = 3.053) and entropy (OR = 17.095) were significant predictors. CONCLUSION: Texture analysis of torn SSTs on preoperative T2-weighted MRA using the GLCM may be helpful to predict postoperative tendon state after rotator cuff repair.

Nonparametric statistical tests for the continuous data: the basic concept and the practical use / 대한마취과학회지

Conventional statistical tests are usually called parametric tests. Parametric tests are used more frequently than nonparametric tests in many medical articles, because most of the medical researchers are familiar with and the statistical software packages strongly support parametric tests. Parametric tests require important assumption; assumption of normality which means that distribution of sample means is normally distributed. However, parametric test can be misleading when this assumption is not satisfied. In this circumstance, nonparametric tests are the alternative methods available, because they do not required the normality assumption. Nonparametric tests are the statistical methods based on signs and ranks. In this article, we will discuss about the basic concepts and practical use of nonparametric tests for the guide to the proper use.

A Statistical Analysis on Forensic Autopsies Performed in Korea in 2015 / 대한법의학회지

The statistical analysis of forensic autopsies provides basic data for the postmortem investigation system and is the foundation of the statistics used in the analysis of the causes of death. A statistical analysis was performed on national forensic autopsy data collected in the Republic of Korea during 2015 to overcome regional limitations and limitations from the number of unusual deaths in the current forensic autopsy research. A total of 6,610 cases were categorized based on the region, requested Police Agency or Coast Guard, gender, age, manner of death, and cause of death. Analysis of the manner of death revealed that 3,326 cases (50.3%) were unnatural death, 2,754 cases (41.7%) were natural death, and 530 cases (8.0%) were of unknown. Of the 3,326 cases of unnatural death, the majority (1,275 cases, 38.3%) were accidents, 1,040 cases (31.3%) were suicide, 481 cases (14.5%) were homicide, and 530 cases (15.9%) were undetermined death. Among the unnatural death, the majority (1,330 cases, 40.0%) were trauma, followed by 588 cases (17.7%) of asphyxia and 566 cases (17.0%) of poisoning. Fall down were the major cause of death by trauma (538 cases, 40.5%). On the basis of a previous study, there were 588 cases of asphyxia; strangulation was the major cause, with 472 cases (80.3%). Of the 2,754 cases of natural death, heart disease was the major cause (1,417 cases, 51.5%), followed by vascular disease (503 cases, 18.3%).

Texture Analysis of Supraspinatus Ultrasound Image for Computer Aided Diagnostic System / 대한의료정보학회지

OBJECTIVES: In this paper, we proposed an algorithm for recognizing a rotator cuff supraspinatus tendon tear using a texture analysis based on a histogram, gray level co-occurrence matrix (GLCM), and gray level run length matrix (GLRLM). METHODS: First, we applied a total of 57 features (5 first order descriptors, 40 GLCM features, and 12 GLRLM features) to each rotator cuff region of interest. Our results show that first order statistics (mean, skewness, entropy, energy, smoothness), GLCM (correlation, contrast, energy, entropy, difference entropy, homogeneity, maximum probability, sum average, sum entropy), and GLRLM features are helpful to distinguish a normal supraspinatus tendon and an abnormal supraspinatus tendon. The statistical significance of these features is verified using a t-test. The support vector machine classification showed accuracy using feature combinations. Support Vector Machine offers good performance with a small amount of training data. Sensitivity, specificity, and accuracy are used to evaluate performance of a classification test. RESULTS: From the results, first order statics features and GLCM and GLRLM features afford 95%, 85%, and 100% accuracy, respectively. First order statistics and GLCM and GLRLM features in combination provided 100% accuracy. Combinations that include GLRLM features had high accuracy. GLRLM features were confirmed as highly accurate features for classified normal and abnormal. CONCLUSIONS: This algorithm will be helpful to diagnose supraspinatus tendon tear on ultrasound images.

Analysis of periodontal data using mixed effects models

A fundamental problem in analyzing complex multilevel-structured periodontal data is the violation of independency among the observations, which is an assumption in traditional statistical models (e.g., analysis of variance and ordinary least squares regression). In many cases, aggregation (i.e., mean or sum scores) has been employed to overcome this problem. However, the aggregation approach still exhibits certain limitations, such as a loss of power and detailed information, no cross-level relationship analysis, and the potential for creating an ecological fallacy. In order to handle multilevel-structured data appropriately, mixed effects models have been introduced and employed in dental research using periodontal data. The use of mixed effects models might account for the potential bias due to the violation of the independency assumption as well as provide accurate estimates.

Análise de Correspondência: bases teóricas na interpretação de dados categóricos em Ciências da Saúde / Correspondence Analysis: a theoretical basis for categorical data interpretation in Health Sciences / Análisis de Correspondencia: bases teóricas para la interpretación de datos categóricos en Ciencias de Salud

Na área biomédica, a ocorrência de dados categóricos é comum, e métodos de análise específicos para este tipo de dado são usados para revelar padrões existentes. A Análise de Correspondência é uma dessas técnicas, utilizada na análise de tabelas de contingência de grande porte. A maioria dos trabalhos publicados em periódicos brasileiros foca apenas na sua interpretação gráfica, não abordando outras potencialidades da técnica. O objetivo do trabalho é mostrar a técnica não limitada à análise gráfica, mas também utilizar estatísticas que permitem sua análise quantitativa. Exemplo mostra que a análise gráfica é enriquecida com a utilização dessas estatísticas, e que a inclusão de uma categoria com baixa ocorrência pode ser considerada como categoria suplementar devido à sua baixa contribuição à inércia. Assim, diminui-se a subjetividade na análise, sendo possível revelar a relação entre as categorias com a análise de resíduos, aspecto este não facilmente observado graficamente. Comparação com a Análise de Componentes Principais mostrou a vantagem da técnica.

Categorical variables are common in the biomedical field, and many descriptive methods have been proposed for revealing intrinsic patterns in data. Correspondence Analysis is an especially useful method for categorical data analysis of large contingency tables. Although numerous studies have been published on this method, most Portuguese-language articles have failed to explore its full potential, focusing only on graphical interpretation. The current paper reviews the method, showing that graphical analysis can be enriched by the right statistics. The article presents the mathematical basis for correspondence analysis and its most frequently used statistics. The procedure has shown that such statistics enrich symmetric map evaluation, that a low relative frequency category can be represented by supplementary category points, and that inertia contributions are highly related to residual analysis of contingency tables, not easily visualized by symmetric maps. Correspondence Analysis has proven advantageous when compared to principal components analysis.

En el campo biomédico, los datos categóricos son frecuentemente utilizados y los métodos de análisis específicos son empleados para revelar patrones intrínsecamente existentes en los mismos. El Análisis de Correspondencias es una de estas técnicas, siendo útil en el análisis de tablas de contingencia con un gran número de clases. A pesar de que muchos artículos han explorado esta técnica, la mayoría de trabajos en revistas brasileñas se centra sólo en su interpretación gráfica. El objetivo de este trabajo es incluir estadísticas que permitan la interpretación cuantitativa de la técnica. Como ejemplo, tenemos el análisis de un mapa simétrico enriquecido con el uso de estadísticas, en el cual la inclusión de una clase de baja ocurrencia puede ser considerada como una categoría suplementaria, debido a su baja contribución a la inercia de datos. Por lo tanto, disminuye la subjetividad en el análisis, siendo posible ahora revelar la relación entre las categorías con el análisis residual, lo que no es fácil observar en los gráficos. La comparación con el análisis de componentes principales mostró sus ventajas.

The Statistical Analysis on Legal Autopsy Performed in Korea during 2013 Year / 대한법의학회지

Medicolegal autopsy is a vital tool for obtaining reliable injury mortality data. This study statistically analyzed data obtained from medicolegal autopsies performed in Korea in 2013. The aim of this study was to analyze various aspects of the 4,861 deaths that were categorized as unusual in Korea in 2013. A total of 4,861 deaths were analyzed by gender, age, manner of death, and cause of death. Of the 4,861 deaths, 3,542 (73.3%) were of men and 1,302 (26.7%) were of women. With respect to the manner of death, 54.4% were recorded as unnatural deaths, 38.8% were natural deaths, and 6.9% had unknown causes. Of the 2,642 unnatural deaths, 45.0% were determined to be accidental deaths, 26.3% suicidal, 16.9% homicidal, and 11.8% undetermined. Of the total number of unnatural deaths, 42.1% were trauma-related deaths, for which falling down accounted for 33.8%. Asphyxiation accounted for 16.0% of unnatural deaths, and of these, the predominant cause was hanging (58.8%). In addition, 14.4% of deaths were due to drowning, 12.9% poisoning, 11.0% thermal injuries, 1.8% complications arising from medical procedures, and 0.8% electrocution, starvation, or neglect. Among the 1,886 natural deaths, heart diseases accounted for 52.0% and vascular diseases accounted for 16.9%. Of the 196 deaths among children under the age of 10 years, 41.8% were recorded as unnatural deaths, 45.1% were natural deaths, and 1.5% had unknown causes.

Statistical methods used in articles published by the Journal of Periodontal and Implant Science

PURPOSE: The purposes of this study were to assess the trend of use of statistical methods including parametric and nonparametric methods and to evaluate the use of complex statistical methodology in recent periodontal studies. METHODS: This study analyzed 123 articles published in the Journal of Periodontal & Implant Science (JPIS) between 2010 and 2014. Frequencies and percentages were calculated according to the number of statistical methods used, the type of statistical method applied, and the type of statistical software used. RESULTS: Most of the published articles considered (64.4%) used statistical methods. Since 2011, the percentage of JPIS articles using statistics has increased. On the basis of multiple counting, we found that the percentage of studies in JPIS using parametric methods was 61.1%. Further, complex statistical methods were applied in only 6 of the published studies (5.0%), and nonparametric statistical methods were applied in 77 of the published studies (38.9% of a total of 198 studies considered). CONCLUSIONS: We found an increasing trend towards the application of statistical methods and nonparametric methods in recent periodontal studies and thus, concluded that increased use of complex statistical methodology might be preferred by the researchers in the fields of study covered by JPIS.

Big Data Analysis Using Modern Statistical and Machine Learning Methods in Medicine / 대한배뇨장애요실금학회지

In this article we introduce modern statistical machine learning and bioinformatics approaches that have been used in learning statistical relationships from big data in medicine and behavioral science that typically include clinical, genomic (and proteomic) and environmental variables. Every year, data collected from biomedical and behavioral science is getting larger and more complicated. Thus, in medicine, we also need to be aware of this trend and understand the statistical tools that are available to analyze these datasets. Many statistical analyses that are aimed to analyze such big datasets have been introduced recently. However, given many different types of clinical, genomic, and environmental data, it is rather uncommon to see statistical methods that combine knowledge resulting from those different data types. To this extent, we will introduce big data in terms of clinical data, single nucleotide polymorphism and gene expression studies and their interactions with environment. In this article, we will introduce the concept of well-known regression analyses such as linear and logistic regressions that has been widely used in clinical data analyses and modern statistical models such as Bayesian networks that has been introduced to analyze more complicated data. Also we will discuss how to represent the interaction among clinical, genomic, and environmental data in using modern statistical models. We conclude this article with a promising modern statistical method called Bayesian networks that is suitable in analyzing big data sets that consists with different type of large data from clinical, genomic, and environmental data. Such statistical model form big data will provide us with more comprehensive understanding of human physiology and disease.

Inappropriate Survey Design Analysis of the Korean National Health and Nutrition Examination Survey May Produce Biased Results / 예방의학회지

OBJECTIVES: The inherent nature of the Korean National Health and Nutrition Examination Survey (KNHANES) design requires special analysis by incorporating sample weights, stratification, and clustering not used in ordinary statistical procedures. METHODS: This study investigated the proportion of research papers that have used an appropriate statistical methodology out of the research papers analyzing the KNHANES cited in the PubMed online system from 2007 to 2012. We also compared differences in mean and regression estimates between the ordinary statistical data analyses without sampling weight and design-based data analyses using the KNHANES 2008 to 2010. RESULTS: Of the 247 research articles cited in PubMed, only 19.8% of all articles used survey design analysis, compared with 80.2% of articles that used ordinary statistical analysis, treating KNHANES data as if it were collected using a simple random sampling method. Means and standard errors differed between the ordinary statistical data analyses and design-based analyses, and the standard errors in the design-based analyses tended to be larger than those in the ordinary statistical data analyses. CONCLUSIONS: Ignoring complex survey design can result in biased estimates and overstated significance levels. Sample weights, stratification, and clustering of the design must be incorporated into analyses to ensure the development of appropriate estimates and standard errors of these estimates.

An analysis of the articles published in the Journal of Korean Academy of Oral Health, from 1995 to 2012 / 대한구강보건학회지

OBJECTIVES: This study proposes to trace the development of the Journal of Korean Academy of Oral Health by analyzing its articles. METHODS: All of the articles published in the Journal of Korean Academy of Oral Health from 1995 to 2012 were assessed and analyzed with regard to the following: research design, MeSH database keywords, and statistical method. RESULTS: The total number of published articles was 830. This journal has conducted based on the relatively weak research designs and statistical analysis, and keyword does not matched with MeSH terms. The most frequently used research design was cross-sectional (53.1%). The statistical methods most often used were the F-test, t-test and contingency table. Only 34.3% of keywords matched MeSH terms. CONCLUSIONS: It was confirmed that the activities of the field of Journal of Korean Academy of Oral Health have become more prevalent over the past 18 years. In order to develop the quality of the journal, more systematic, refined study designs and methods are needed. It is also urgently essential that authors understand MeSH terms, and the Journal of Korean Academy of Oral Health should request that authors use accurate MeSH terms as their keywords when they submit articles.