Metanálises em psicologia: uma introdução conceitual e prática / Meta-analyses in psychology: a conceptual and hands-on introduction / Metanálisis en psicología: una introducción conceptual y práctica

Metanálise consiste em um conjunto de técnicas estatísticas que visa integrar os resultados de dois ou mais estudos primários. Ela permite produzir estimativas pontuais e intervalares de algum parâmetro populacional, geralmente uma medida de tamanho de efeito. Este artigo tem como objetivo apresentar conceitos fundamentais sobre metanálise e suas aplicações para psicólogos e estudantes de psicologia. O artigo: (1) introduz a lógica da metanálise, seus potenciais e as críticas a ela endereçadas; (2) apresenta dois modelos de metanálise comumente usados por pesquisadores; e (3) aborda dois tópicos importantes para a interpretação correta dos resultados: heterogeneidade e análise de subgrupos. Um exemplo fictício ilustra os conceitos ao longo do artigo. Os Materiais Suplementares contêm equações dos modelos apresentados no texto, resultados comentados de uma síntese metanalítica, código na linguagem R para reproduzir resultados e figuras desse artigo e uma breve lista comentada de fontes adicionais sobre metanálise. (AU)

Meta-analysis consists of a set of statistical techniques that aims to combine the results of two or more primary studies. It enables the calculation of point and interval estimates of some population parameter, usually a measure of effect size. The aim of this article is to introduce fundamental concepts of meta-analysis and its applications for psychologists and psychology students. The article: (1) introduces the logic of meta-analysis, its uses and common criticisms levied against it; (2) presents two computational models of meta-analysis commonly used by researchers; and (3) addresses two issues associated with the correct interpretation of results from meta-analyses: heterogeneity and subgroup analysis. A worked example illustrates the concepts throughout the article. The Supplementary Materials contain a worked example of the models presented in the text, a script in R language that allows the reader to reproduce the results, and a commented list of additional sources. (AU)

El metanálisis consiste en un conjunto de técnicas estadísticas que tiene como objetivo integrar los resultados de dos o más estudios primarios. Permite producir estimaciones puntuales y de intervalo de algún parámetro de población, generalmente una medida del tamaño del efecto. Este artículo presenta conceptos fundamentales sobre el metanálisis y sus aplicaciones para psicólogos y estudiantes de psicología. El artículo: (1) introduce la lógica del metanálisis, sus potencialidades y las críticas que se le dirigen; (2) presenta dos modelos de metanálisis comúnmente utilizados por los investigadores; y (3) aborda dos temas importantes para la correcta interpretación de los resultados: heterogeneidad y análisis de subgrupos. Un ejemplo ficticio ilustra los conceptos a lo largo del artículo. Los Materiales Suplementarios contienen ecuaciones de los modelos presentados en el texto, resultados comentados de una síntesis metanalítica, código en el lenguaje R para reproducir los resultados y las figuras de este artículo, y una breve lista comentada de fuentes adicionales. (AU)

Teste de inteligência não verbal R-1: o tamanho do efeito para as normas de 2018 / R-1 non-verbal intelligence test: the effect size for the 2018 standards

O estudo apresenta os tamanhos do efeito, seus intervalos de confiança, classificações e visualizações para a atualização normativa de 2018 do Teste não verbal de Inteligência R-1, visto que as diferenças estatisticamente calculadas com base no valor p oferecerem evidências tênues contra a hipótese nula e, por isso, não servem como uma prova da significância clínica. Utilizou-se a amostra normativa do instrumento, composta por 5.595 adultos, de ambos os sexos, com idades entre 18 e 65 anos, provenientes das cinco regiões geográficas brasileiras e subdivididos pelos níveis de ensino fundamental, médio e superior. Os resultados apontaram tamanhos do efeito entre médios e grandes na comparação entre os níveis de ensino fundamental e médio; grande a muito grande na relação entre o ensino fundamental e o superior e; pequenos a médios entre os níveis médio e superior de ensino. Concluiu-se que as diferenças estatisticamente observadas, por meio das análises de variância e pos-hoc de Tukey refletem um efeito real quando se considera o impacto da variável nível de escolaridade no desempenho do teste. Entendeu-se que os estudos normativos do instrumento refletem um impacto real quando se considera a variável em estudo, devendo incluir o tamanho do efeito e seus respectivos intervalos de confiança.

The study presents the effect sizes, their confidence intervals, ratings, and visualizations for the 2018 normative update of the R-1 Nonverbal Intelligence Test, since the statistically calculated differences based on the p-value offer tenuous evidence against the null hypothesis and do not serve as a proof of clinical significance. We used the normative sample of the instrument, consisting of 5,595 adults of both sexes, aged 18 to 65 years, from the five Brazilian geographic regions and subdivided by elementary, middle, and high school levels. The results showed medium to large effect sizes in the comparison between elementary and high school levels; large to very large in the relation between elementary and high school; and small to medium effect sizes between high school and high school levels. It was concluded that the statistically observed differences, by means of variance and Tukey's post-hoc analyses reflect a real effect when considering the impact of the education level variable on test performance. It was understood that normative studies of the instrument reflect a real impact when considering the variable under study, and should include the effect size and their respective confidence intervals.

Altered white matter microarchitecture in Parkinson's disease: a voxel-based meta-analysis of diffusion tensor imaging studies / 医学前沿

This study aimed to define the most consistent white matter microarchitecture pattern in Parkinson's disease (PD) reflected by fractional anisotropy (FA), addressing clinical profiles and methodology-related heterogeneity. Web-based publication databases were searched to conduct a meta-analysis of whole-brain diffusion tensor imaging studies comparing PD with healthy controls (HC) using the anisotropic effect size-signed differential mapping. A total of 808 patients with PD and 760 HC coming from 27 databases were finally included. Subgroup analyses were conducted considering heterogeneity with respect to medication status, disease stage, analysis methods, and the number of diffusion directions in acquisition. Compared with HC, patients with PD had decreased FA in the left middle cerebellar peduncle, corpus callosum (CC), left inferior fronto-occipital fasciculus, and right inferior longitudinal fasciculus. Most of the main results remained unchanged in subgroup meta-analyses of medicated patients, early stage patients, voxel-based analysis, and acquisition with 30 diffusion directions. The subgroup meta-analysis of medication-free patients showed FA decrease in the right olfactory cortex. The cerebellum and CC, associated with typical motor impairment, showed the most consistent FA decreases in PD. Medication status, analysis approaches, and the number of diffusion directions have an important impact on the findings, needing careful evaluation in future meta-analyses.

Metodologías cuantitativas: Cálculo del tamaño de muestra con STATA y R / Quantitative methods: Sample size calculation with STATA and R

El cálculo de tamaño de muestra es un aspecto esencial del diseño de estudios cuantitativos. Un adecuado tamaño de muestra nos permite determinar cuál es la mínima cantidad de participantes necesarios para probar nuestra hipótesis de interés. De esta manera, podemos reducir costos, maximizar el uso de nuestros recursos de investigación y garantizar la factibilidad del estudio. Contradictoriamente, a pesar de su relevancia muy pocos investigadores dominan esta habilidad. Esta revisión tiene por objeto revisar los conceptos básicos para realizar un cálculo de tamaño de muestra y compartir códigos de Stata y R específicamente diseñados para facilitar estos cálculos.

The calculation of sample size is an essential aspect of the design of quantitative studies. An adequate sample size allows us to determine the minimum number of participants necessary to test our hypothesis of interest. Hence, we can reduce costs, maximize the use of our research resources and guarantee the feasibility of the study. Contradictorily, despite its relevance, very few researchers dominate this skill. This review aims to review the basics of sample size calculation and share Stata and R codes specifically designed to facilitate these calculations.

Estimación de la magnitud del efecto en invarianza de medición / Estimation of effect size in measurement invariance / Avaliação do tamanho do efeito na invariância de medida

Este trabajo presenta un programa en MS Excel® para evaluar la magnitud del efecto (ES, por las siglas en inglés) en invarianza de medición de diferentes parámetros como las cargas factoriales, interceptos/thresholds y residuales, con base en estadísticos estandarizados ya conocidos. El funcionamiento del programa y la interpretación de las medidas de ES se ejemplificaron con datos empíricos.

This paper presents a MS Excel® program for estimating effect size (ES) in the measurement invariance of different item parameters, such as the factor loadings, intercepts/thresholds and residuals, based in well-known standardized statistics. Examples with real data are provided for the functioning of the program and the interpretation of the ES measures.

Este artigo apresenta um programa no MS Excel® para avaliar o tamanho do efeito (ES, pela sigla em inglês) na invariância de medida de diferentes parâmetros dos itens, como cargas fatoriais, interceptos/thresholds e resíduos, com base em estatísticas padronizadas bem conhecidas. O funcionamento do programa e interpretação das medidas de ES é exemplificado com dados empíricos.

Gender differences in binaural speech-evoked auditory brainstem response: are they clinically significant? / Diferenças de gênero no potencial evocado auditivo de tronco encefálico com estímulo de fala binaural: são clinicamente significantes?

Abstract Introduction: Binaurally evoked auditory evoked potentials have good diagnostic values when testing subjects with central auditory deficits. The literature on speech-evoked auditory brainstem response evoked by binaural stimulation is in fact limited. Gender disparities in speech-evoked auditory brainstem response results have been consistently noted but the magnitude of gender difference has not been reported. Objective: The present study aimed to compare the magnitude of gender difference in speech-evoked auditory brainstem response results between monaural and binaural stimulations. Methods: A total of 34 healthy Asian adults aged 19-30 years participated in this comparative study. Eighteen of them were females (mean age = 23.6 ± 2.3 years) and the remaining sixteen were males (mean age = 22.0 ± 2.3 years). For each subject, speech-evoked auditory brainstem response was recorded with the synthesized syllable /da/ presented monaurally and binaurally. Results: While latencies were not affected (p > 0.05), the binaural stimulation produced statistically higher speech-evoked auditory brainstem response amplitudes than the monaural stimulation (p < 0.05). As revealed by large effect sizes (d > 0.80), substantive gender differences were noted in most of speech-evoked auditory brainstem response peaks for both stimulation modes. Conclusion: The magnitude of gender difference between the two stimulation modes revealed some distinct patterns. Based on these clinically significant results, gender-specific normative data are highly recommended when using speech-evoked auditory brainstem response for clinical and future applications. The preliminary normative data provided in the present study can serve as the reference for future studies on this test among Asian adults.

Resumo Introdução: Potenciais auditivos evocados de modo binaural apresentam bons valores diagnósticos ao testar indivíduos com déficits auditivos centrais. A literatura sobre a resposta do potencial evocado do tronco encefálico com estímulo de fala de modo binaural é, de fato, limitada. As diferenças de gênero nos resultados desse exame têm sido consistentemente observadas, mas a magnitude da diferença de gênero ainda não foi relatada. Objetivo: Comparar a magnitude da diferença de gênero nos resultados do potencial evocado do tronco encefálico com estímulo de fala entre estímulos monaural e binaural. Método: Um total de 34 adultos asiáticos saudáveis com idades entre 19 e 30 anos participaram deste estudo comparativo. Dezoito deles eram do sexo feminino (média de idade = 23,6 ± 2,3 anos) e os outros dezesseis do sexo masculino (média de idade = 22,0 ± 2,3 anos). Para cada indivíduo, o potencial evocado do tronco encefálico com estímulo de fala foi registrado com a sílaba sintetizada /da/ apresentada de forma monaural e binaural. Resultados: Embora as latências não tenham sido afetadas (p > 0,05), a estimulação binaural produziu amplitudes de potencial evocado do tronco encefálico com estímulo de fala estatisticamente maiores do que a estimulação monaural (p < 0,05). Como demonstrado pelos grandes tamanhos de efeito (d > 0,80), diferenças substanciais de gênero foram observadas na maioria dos picos de potencial evocado do tronco encefálico com estímulo de fala para ambos os modos de estímulo. Conclusão: A magnitude da diferença de gênero entre os dois modos de estímulo revelou alguns padrões distintos. Com base nesses resultados clinicamente significantes, os dados normativos específicos para o gênero são altamente recomendados quando se usa o potencial evocado do tronco encefálico com estímulo de fala para aplicações clínicas e futuras. Os dados normativos preliminares fornecidos pelo presente estudo podem servir como referência para futuros estudos sobre esse exame em asiáticos adultos.

Teste de hipóteses: perguntas que você sempre quis fazer, mas nunca teve coragem / Hypothesis testing: questions you have always wanted to ask, but never had the courage to

Dando continuidade aos artigos da série "Perguntas que você sempre quis fazer, mas nunca teve coragem", que tem como objetivo responder e sugerir referências para o melhor entendimento das principais dúvidas dos pesquisadores do Hospital de Clínicas de Porto Alegre sobre estatística, este segundo artigo se propõe a responder às principais dúvidas levantadas sobre Teste de Hipóteses. São discutidas questões referentes à metodologia de um teste de hipóteses na concepção clássica de Inferência Estatística, bem como tamanho de efeito, tipos de erros, valor de p e poder. Os conceitos são abordados numa linguagem acessível ao público leigo e diversas referências são sugeridas para os curiosos em relação ao tema. (AU)

Continuing the series of articles "Questions you have always wanted to ask, but never had the courage to", which aims to answer the most common questions of researchers at Hospital de Clínicas de Porto Alegre regarding statistics and to suggest references for a better understanding, this second article addresses the topic of hypothesis testing. The hypothesis testing method is discussed from a classical conception of statistical inference, including effect size, type of errors, p-value and power. The concepts are explained in plain language for lay readers and several references are suggested for those curious about the topic. (AU)

Test-retest reliability and responsiveness of a Malay tinnitus questionnaire

Introduction: Tinnitus is a common complaint amongpatients with ear diseases and can be serious if not treated.Recently, a Malay tinnitus questionnaire, known as the“Borang Evaluasi Soal selidik Tinnitus” (BEST) had beendeveloped and preliminarily validated among Malayspeakingpopulation. The aims of the present study were todetermine the test-retest reliability and responsiveness ofthe BEST questionnaire.Method: Forty-six Malay adults (aged 23-74 years) withtinnitus were enrolled. They were instructed to fill in theBEST questionnaire accordingly. After one week, 21 of themwere asked to fill in the questionnaire again. The other 25subjects underwent tinnitus intervention for three monthsand following this; the BEST was administered to themagain.Results: In the test-retest reliability task, the intraclasscorrelation values obtained were acceptably high (0.70-0.90).After the intervention, significant differences in the BESTresult were found in the mind domain, main domain andcomposite score (p<0.05) with moderate effect sizes (0.61-0.70).Conclusion: The test-retest reliability of the BEST was foundto be good. It also showed good responsiveness tointervention. The clinical usefulness of the BEST inassessing patients with tinnitus was further supported bythe present study.nnaire; reliability; responsiveness; effect size

An alternative approach to measure effect size / Uma medida alternativa de tamanho de efeito

The aim of this paper is to present an alternative approach to measure effect size. The model proposed belongs to r family....(AU)

O objetivo deste artigo é apresentar uma medida alternativa de cálculo de tamanho de efeito. o modelo proposto pertence a família r....(AU)

La información situacional probabilística en el deporte: un metaanálisis / Situational probability information in sport: A meta-analysis

Resumen El objetivo del estudio es cuantificar el efecto de la información situacional probabilística (ISP) sobre el rendimiento deportivo y en concreto sobre el inicio en el tiempo de respuesta y la precisión de los deportistas. Existe evidencia científica de que los deportistas de mayor nivel deportivo desarrollan la habilidad perceptiva para usar la ISP, realizando comportamientos anticipatorios, si bien se desconoce la magnitud de dicho efecto. Se realiza un metaanálisis de efectos aleatorios para cuantificar el tamaño del efecto (TE) de la ISP en el comportamiento motor de los deportistas. Los resultados muestran un TE medio final grande de 1.29 para el tiempo de respuesta (en 7 estudios y 252 participantes) y de 1.31 para la precisión (en nueve investigaciones y 292 participantes), seleccionados de acuerdo con los criterios establecidos. Con la limitación del reducido número de estudios analizados (n = 9), los resultados indican que los deportistas expertos anticipan más respuestas y con más precisión que los noveles debido al uso de la ISP. Se recomienda entrenar perceptivamente la identificación y el uso de la ISP a nivel deportivo, ya que aquellos deportistas que hagan un mejor uso de esta información contextual podrán anticipar sus respuestas con precisión.

Abstract The aim of the study is to quantify the effect of Situational Probability Information (SPI) on athletic performance, specifically on the onset of the response time and the accuracy of athletes. There is scientific evidence that shows that higher sport level athletes develop the perceptive skills to use SPI, thereby performing anticipatory behaviors. However, the magnitude of this effect remains unknown. A meta-analysis of random effects was carried out to quantify the effect size (ES) of SPI on the motor behavior of athletes. The results showed an overall final mean ES of 1.29 for the response time (in 7 studies and 252 participants), and 1.31 for accuracy (in 9 studies and 292 participants), according to the criteria established. With the limitation of the low number of studies analyzed (n = 9), the results suggest that expert athletes anticipate more frequently and with higher accuracy than beginners, due to the use of SPI. It is recommended to train in the identification and use of the SPI in the sports domain, as athletes who use this contextual information more effectively could anticipate the responses with precision.

<b>Effectiveness of Acupuncture Therapy on </b><i><b>Hiesho </b></i><b>(Cold Disorder) in Maturate Stage Females : A Multicenter, Randomized, Prospective, Controlled T</b><b>rial</b> / 日本東洋医学雑誌

<p><b>Objective </b>: To determine the effectiveness of acupuncture therapy on <i>hiesho </i>in maturate stage females.<br> <b>Design </b>: Multicenter, randomized, prospective, open blind, waiting list-controlled trial.<br><b>Setting </b>: A clinical center attached to three universities and one vocational school.<br><b>Participants </b>: Twenty two females between 18-39 years of age and with a level of more than four points on the “<i>hiesho </i>sensation scale” proposed by Kusumi et al for <i>hiesho</i>. <b>Interventions </b>: Participants were randomly assigned to receive therapies of either acupuncture or no therapy (waiting list controls). Acupuncture therapy was provided by needle retention to SP 6 and electro-acupuncture therapy to BL 32 at a frequency of 1 Hz for 20 minutes. One session per week of this therapy was provided for a total of four sessions. <b>Method of Measurement </b>: The primary outcome of change in <i>hiesho </i>intensity was measured using the visual analogue scale (VAS). Secondary changes were measured by an eight heading score and three component summaries of the standard edition SF-36 v 2.<br><b>Results </b>: The statistical analyses used an intent-to-treat analysis that included two participants who dropped out, and the mixture of one participant targeted for exclusion who was censored from the analyses. As a result, 21 participants were classified as either in the acupuncture group (n = 12) or the control group (n = 9). Efficacy with acupuncture therapy was not found for effect size (Cohen <i>d</i>, point-biserial correlation <i>r</i>) for VAS and the scores of SF-36 between the two groups.<br><b>Conclusions </b>: Effectiveness of the acupuncture therapy was not found, which suggests that it may be due to the smaller sample size, frequency of intervention, and symptoms associated with autonomic dysfunction.</p>

A Review on the Use of Effect Size in Nursing Research

PURPOSE: The purpose of this study was to introduce the main concepts of statistical testing and effect size and to provide researchers in nursing science with guidance on how to calculate the effect size for the statistical analysis methods mainly used in nursing. METHODS: For t-test, analysis of variance, correlation analysis, regression analysis which are used frequently in nursing research, the generally accepted definitions of the effect size were explained. RESULTS: Some formulae for calculating the effect size are described with several examples in nursing research. Furthermore, the authors present the required minimum sample size for each example utilizing G*Power 3 software that is the most widely used program for calculating sample size. CONCLUSION: It is noted that statistical significance testing and effect size measurement serve different purposes, and the reliance on only one side may be misleading. Some practical guidelines are recommended for combining statistical significance testing and effect size measure in order to make more balanced decisions in quantitative analyses.

Celebrity Suicides and Their Differential Influence on Suicides in the General Population: A National Population-Based Study in Korea

OBJECTIVE: Although evidence suggests that there is an increase in suicide rates in the general population following celebrity suicide, the rates are heterogeneous across celebrities and countries. It is unclear which is the more vulnerable population according to the effect sizes of celebrity suicides to general population. METHODS: All suicide victims in the general population verified by the Korea National Statistical Office and suicides of celebrity in South Korea were included for 7 years from 2005 to 2011. Effect sizes were estimated by comparing rates of suicide in the population one month before and after each celebrity suicide. The associations between suicide victims and celebrities were examined. RESULTS: Among 94,845 suicide victims, 17,209 completed suicide within one month after 13 celebrity suicides. Multivariate logistic regression analyses revealed that suicide victims who died after celebrity suicide were significantly likely to be of age 20-39, female, and to die by hanging. These qualities were more strongly associated among those who followed celebrity suicide with intermediate and high effect sizes than lower. Younger suicide victims were significantly associated with higher effect size, female gender, white collar employment, unmarried status, higher education, death by hanging, and night-time death. Characteristics of celebrities were significantly associated with those of general population in hanging method and gender. CONCLUSION: Individuals who commit suicide after a celebrity suicide are likely to be younger, female, and prefer hanging as method of suicide, which are more strongly associated in higher effect sizes of celebrity suicide.

Doing meta-analysis in research: A systematic approach.

Meta-analysis is an objective, systematic review that employs statistical methods to combine and summarize the results of several studies. It is a quantitative synthesis of all the unbiased evidence, meant for summarizing large volume of data, establishing and determining the magnitude of an effect, and to increase power and precision of studies. The steps to performing a meta-analysis include making a hypothesis and defining the domain of research, defining inclusion/exclusion criteria, literature search, selecting the final set of studies, extracting data on variables of interest, coding procedures, calculating effect sizes and interpretations, selecting potential moderators and examine their relationships, report writing, and critical evaluation. Meta-analysis has several strengths as well as weaknesses.

Cliff´s Delta Calculator: un programa para calcular el tamaño del efecto no paramétrico al comparar dos grupos de observaciones / Cliff´s Delta Calculator: a non-parametric effect size program for two groups of observations

El estadístico Delta de Cliff permite cuantificar la magnitud de la diferencia entre dos grupos de observaciones que resultan incompatibles con el presupuesto de normalidad. El análisis de esta cuantificación complementa la interpretación del p-valor asociado a la correspondiente prueba de hipótesis. La aplicación de medidas del tamaño del efecto ha sido promovida durante las últimas décadas tanto por metodólogos, como por instituciones líderes en las ciencias del comportamiento. El propósito de la presente contribución es presentar un programa denominado Cliff's Delta Calculator que es capaz de calcular y graficar el valor del tamaño del efecto no paramétrico para dos grupos de observaciones. Se ofrece una comparación de este programa con otras calculadoras comerciales y no comerciales actualmente disponibles. Se describe su funcionamiento, sus fundamentos matemáticos y se presentan y discuten dos ejemplos de aplicación en la investigación psicológica. Se concluye que este programa presenta algunas ventajas en comparación con otras calculadoras comerciales disponibles.

The Cliff’s Delta statistic is a non-parametric effect size measure that quantifies the amount of difference between two groups of observations beyond p-values interpretation. This measure can be understood as a useful complementary analysis for the corresponding hypothesis testing. During the last two decades the use of effect size measures has been strongly encouraged by methodologists and leading institutions of behavioral sciences. The aim of this contribution is to introduce the Cliff’s Delta Calculator software that performs such analysis and offers some interpretation tips. Differences and similarities with the parametric case are analysed and illustrated. The implementation of this free program is fully described and compared with other calculators. Alternative algorithmic approaches are mathematically analysed and a basic linear algebra proof of its equivalence is formally presented. Two worked examples in cognitive psychology are commented. A visual interpretation of Cliff’s Delta is suggested. Availability, installation and applications of the program are presented and discussed.

Estudio preliminar del impacto socioeconómico sobre los puntajes de una batería multidimensional de aptitudes en niños preescolares / A preliminary study on the socioeconomic impact on the scores of a set of multidimensional aptitude tests in pre-school children

El presente estudio explora las relaciones entre nivel socioeconómico, género y tipo de centro educativo preescolar y el desempeño cognitivo de niños preescolares (N = 323) de Lima (Perú), con una prueba multidimensional de aptitudes. Con la aplicación de la técnica multivariada de análisis de perfiles se hallaron diferencias estadísticamente significativas y de moderada magnitud del efecto en los puntajes cognitivos, debidas a la ubicación del centro educativo; no se detectaron diferencias que se atribuyan al género y al tipo de centro. Se trabajó en base a tres hipótesis: La primera es la hipótesis de igualdad de niveles, en la que se examinan las diferencias que en promedio existen entre los dos grupos. La segunda es la hipótesis de igualdad de la dispersión, que examina si las variables de respuesta (puntajes en las subescalas) tienen la misma respuesta en promedio. Y la tercera, la hipótesis de paralelismo, que prueba si el patrón de elevaciones en el perfil es similar entre los dos grupos. Los resultados fueron evaluados con respecto a la consistencia interna y a la definición del nivel socioeconómico (ubicación geográfica). Se discuten las diferencias halladas en el aspecto socioeconómico y relacionándolas con la bibliografía sobre el tema y la utilidad de la batería multidimensional de aptitudes para niños preescolares. Es importante destacar que el estudio reporta información normativa acerca del desempeño de los niños preescolares, en lo que respecta al género y ubicación de los centros educativos y su carácter correlacional y la magnitud del efecto de los resultados.

The present study explores the relationship between socioeconomic level, gender and type of pre-school education center, and cognitive development in 323 pre-schoolers in Lima (Perú), using a multidimensional aptitude test. By applying the multivariate technique, we found statistical significant differences and medium size effects on the cognitive scores due to the educational center location, whereas gender and type of educational center differences were not found. The results were considered taking into account reliability levels and also according to the definition of socioeconomic levels. The differences found are discussed based on other articles as well as on the usefulness of the multidimensional aptitude tests for pre-schoolers. The sample consisted of 323 children of 5 years old, 167 boys and 156 girls, who go to both private and public pre-schools in a district of Lima. The proportion of public pre-school students (67.2%) was double the amount of private pre-school students (32.8%). Moreover, the private pre-schools had been recently formed (4 to 5 years before) and had children from families with a medium or medium to low socioeconomic level. In order to assess general and relevant aspects of pre-school learning, we applied a pre-school diagnostic test (De la Cruz, 1991), which can be used at a pre-school level (4-5 year-olds). This test contains the following areas: Verbal concepts, Quantitative concepts and Auditive memory, Visual perceptual aptitude and Visual-motor coordination. It is a potentia test because the time varies from one student to another so as to allow every child to answer every item. Furthermore, it is also a maximum performance test because the student tries to obtain the best possible score. We contacted several educational centers (private and public) from three different districts in Lima which accepted to participate in this study. The time of application of the test varied considering: individual skills, the number of children in the collective application, the presence of a teacher's aide for the collective application, and the attitude and motivation of the students. We used MANOVA to analyze profiles, a post hoc univariate contrast, and effect size estimations such as Cohen's d. Our study was based on three hypotheses: The first hypothesis was on the equality of levels (variability between subjects) that explores the differences that exist between both groups separately. As a result, we found no correlation between test performance and gender or school location. However, when considering type of school (public or private), we did find significant differences in one scale: Auditive memory, which was higher in public schools. The second hypothesis was the equality of dispersion (within-group differences), to identify if the answer variables have the same answers on average. We found similarities regarding school conditions (public or private); but there were small differences between gender and school location. The third hypothesis was regarding parallelism, which tests whether the pattern of elevations on the profile is similar between the two groups or not. We did not find important statistical dispersions and the effect size was small. The results coincide with other studies on the correlation between gender and socioeconomic level, and cognitive development. Among some of the limitations of our study, we list the following: for example, we used the school location to determine the children's socioeconomic level. Therefore, there were also extreme scores (outliers), which could vary the central tendency estimations and the dispersion. However, they were not trimmed, since in a previous unreported analysis without these data, researchers found only minimum changes. We also had occasional difficulties in applying the tests, due to the children's disposition to participate as well as their reaction concerning the test situation, which could have added random error on the results. However, we presume their negative reactivity was reduced because of the playful manner in which the tests were presented. The results of our research shed normative information regarding the performance of preschoolers due to gender and location of their educational centers. It is important to emphasize correlations as well as effect size of the results so as not to reach erroneous conclusions.

Meta-Analysis: Some Clinical and Statistical Contributions in Several Medical Disciplines

Meta-analysis in its present form of statistically integrating information from several studies all with a common underlying theme has been around for over 25 years. The medical field has seen many attempts by many investigators to pull summary data together from various sources within a discipline with the goal of making some definitive statement about the state of the science in that discipline. Likewise authors of manuscripts in the background and rationale section of their paper always summarize what they believe to be the state of affairs up to the time of the presentation of their own results in that particular paper. The new data and results they present in their current publication is an attempt to update the progress in that field. Thus in a sense they have performed a partial meta- analysis of summarizing information from the past, presenting their added contribution and thus updating the knowledge base. They have not quite integrated past data in a rigorous statistical way with their new data, but have merely used the data history to justify their current research which pretty much stands on its own. Thus meta-analysis is an after the fact attempt to pull together the current knowledge base whether it be publications or raw data and present a statistical synthesis of all the information and reach a conclusion as to the best treatment or intervention strategy based on all these past contributions. Now it's time to look back at some of these meta-analyses and determine what contributions, if any, they have made to the knowledge base within certain medical disciplines. Many disciplines including psychiatry have been visited by meta- analysis. One now examines some of these studies in the areas of oncology, orthopedics, psychiatry, pediatrics and cardiology. The purpose is to determine, given the information presented, what contributions, statistical challenges and peripheral issues in these disciplines have been brought to light in these meta- analyses.

Responsiveness and precision of Gross Motor Function Measure(66 items version) / 中国康复理论与实践

@#ObjectiveTo compare the responsiveness and precision between the 66 items version of Gross Motor Function Measure(GMFM-66) and 88 items version(GMFM-88).Methods173 children with cerebral palsy(male 126,female 47) who have received twice assessments were involved.All the second assessment were performed 3.8±4.3 months later.112 children received the third assessment 3.2±2.2 months after the second assessment.The effect size and relative precision between the GMFM-66 and GMFM-88 were analyzed.ResultsThe effect size of GMFM-66 between every two assessments was nearly the same as those of GMFM-88.The precision of GMFM-66 was not lower than that of GMFM-88.ConclusionThe interval-scale GMFM-66 has satisfying responsiveness and precision.It is more useful than GMFM-88 in measuring the treating effect of children with cerebral palsy.

Randomized Controlled Trials for Creating Scientific Evidence of the Efficacy and Safety of Complementary and Alternative Medicine / 日本補完代替医療学会誌

It is well known all over the world that the randomized controlled trial (RCT), is the only study design for experiments involving human subjects that can create evidence of the highest quality regarding the efficacy and safety of a new treatment. In Japan, however, most clinical researchers have shown no interest in RCT and thus the number of good RCTs is quite small. Although the recent development of evidence-based medicine has played a role in promoting RCT among clinical researchers, the number of researchers who can understand what an RCT is, design one properly and analyze data appropriately is also quite small. This situation is also completely applicable to the world of complementary and alternative medicine. In this paper, we shall introduce the reader to the concepts behind RCT and a statistical way of thinking that is indispensable for properly conducting RCT to glean scientific evidence of the efficacy and safety of complementary and alternative medicine.<br>

Personality and Crime: A Meta-analysis of Studies on Criminals' Personality / 中国心理卫生杂志

Objective: To review studies on criminals' personality which used EPQ as measurement.Methods:Meta-analysis was used to review 33 studies.Results:Mean effect size delta of four dimensions (P, E, N, L) were 0.62,0.06,0.61,-0.14 in turn.Conclusions:Criminals have significantly higher level on psychoticism and neuroticism than others. There is no significant difference between the criminals and the commons because of heterogeneity of criminous types.