BioRssay: an R package for analyses of bioassays and probit graphs.

Dose-response relationships reflect the effects of a substance on organisms, and are widely used in broad research areas, from medicine and physiology, to vector control and pest management in agronomy. Furthermore, reporting on the response of organisms to stressors is an essential component of many public policies (e.g. public health, environment), and assessment of xenobiotic responses is an integral part of World Health Organization recommendations. Building upon an R script that we previously made available, and considering its popularity, we have now developed a software package in the R environment, BioRssay, to efficiently analyze dose-response relationships. It has more user-friendly functions and more flexibility, and proposes an easy interpretation of the results. The functions in the BioRssay package are built on robust statistical analyses to compare the dose/exposure-response of various bioassays and effectively visualize them in probit-graphs.

Students' perceptions of biostatistics following integration into an evidence-based medicine course series.

BACKGROUND AND PURPOSE: Student pharmacists are expected to demonstrate an understanding of commonly employed statistical tests. This study describes the integration of biostatistics in an evidence-based medicine course series using a learner-centered model tailored to students' needs and interests. EDUCATIONAL ACTIVITY AND SETTING: This course series included thirteen two-hour biostatistics sessions focused on interpreting results and critiquing statistical methods. Three lab sessions were also included, which focused on producing summary reports from clinical data. Journal club presentations were the key method of assessing knowledge. A survey to evaluate students' perceptions of the course and their level of confidence in applying biostatistical concepts was administered twice to measure change over time within two student cohorts. FINDINGS: Results of the survey showed that a significantly higher proportion of students agreed they understood the analyses covered in class (97% vs. 44%, p < 0.001) and felt more confident interpreting results (82% vs. 41%, p < 0.001) in their third year compared to the second year. Students who agreed that they learned important skills for future practice had a significantly higher mean exam score (82.5% vs. 76.2%, p = 0.001). SUMMARY: The results indicate an improvement in the students' perceptions over time with regards to knowledge and usefulness of the course content. Although, integrating biostatistics in a literature-evaluation course is common, this is the first study that evaluated teaching it in more than one semester beyond inclusion in assessment rubrics.

Fundamentos para la aplicación de Bioestadística en Odontología / Fundamentals for the application of Biostatistics in Dentistry

La estadística es una ciencia que resulta transversal a todas las áreas; en salud su aplicación está dada en el diagnóstico, pronóstico y caracterización de factores de riesgo de una enfermedad entre otras cosas, así como también, en salud pública e investigación científca constituye una herramienta fundamental. Por este motivo, resulta sumamente importante su interpretación y comprensión por parte de todos los odontólogos. Si bien existen muchos textos al respecto, muy pocos presentan aplicación en el área de odontología, por lo que muchas veces resulta sumamente difícil la transferencia de estos conceptos a aplicaciones prácticas. Es por eso que se desarrollarán algunos conceptos básicos para posteriormente continuar en sucesivas publicaciones con la educación continua en estadística, con la intención de contribuir con la formación del odontólogo en dicha área y aclarar los conceptos claves. Palabras clave: Educación Continua en Odontología­Estadística ­ Técnicas

Statistics is a science that is transversal to all areas; health application is given in the diagnosis, prognosis and characterization of risk factors for a disease among other things, as well as in public health and scientifc research is an essential tool. For this reason, it is extremely important to the interpretation and understanding by all dentists. While there are many texts about it, few have application in the feld of dentistry, so often extremely diffcult to transfer these concepts to practical applications. That's why some basic concepts will be developed and then continue in subsequent publications with continuing education in statistics, with the intention of contributing to the formation of the dentist in this area and clarify key concepts. Keywords: Education, Dental, Continuing­ Statistics ­ Techniques

Estadística Piloto: paquete estadístico digital educacional para las investigaciones epidemiológicas / Pilotos statistics: a digital-educational statistical package for the epidemiological researches

El uso práctico de la Bioestadística es una preocupación de cualquier investigador. Con el objetivo de facilitar el cálculo matemático de las pruebas estadísticas utilizadas en las investigaciones epidemiológicas, su aplicación e interpretación, se confeccionaron cuatro herramientas, utilizando el software libre y no propietario OpenOffice.org.Calc 2.3 del sistema operativo Unix Ubuntu 8.04 de Linux (con copia a Microsoft Office Excel para su generalización) y con el título: ESTADÍSTICA PILOTO. PAQUETE ESTADÍSTICO DIGITAL EDUCACIONAL PARA LAS INVESTIGACIONES EPIDEMIOLÓGICAS, en Pinar del Río en el 2008. El software contiene 18 pruebas estadísticas: Ji cuadrado (incluye Corrección de Yates), test de probabilidad exacta de Fisher, Odds Ratio, riesgo relativo, sensibilidad, especificidad, valor predictivo de la prueba positiva y negativa, riesgo atribuible, riesgo atribuible porcentual e índices de Kappa y Youden, pruebas dependientes de los valores a-b-c-d de la tabla de contingencia 2x2, además, el cálculo de media, desviación estándar, varianza, estadígrafo Z y Ji cuadrado de Mc Nemar. Las herramientas fueron validadas mediante programas profesionales y generalizados en trabajos de terminación de las especialidades y maestrías y en otras investigaciones de la provincia. Las herramientas fueron presentadas en los eventos provinciales nacionales y en Sudáfrica (2007) y son las médulas de los cursos de postgrado de Bioestadística aplicada del autor, sin sustituir los programas profesionales, sino que se suman a ellos para facilitar el aprendizaje de la Bioestadística. Sus ventajas son la sencillez, aplicabilidad e inmediatez, los resultados al unísono, la facilidad de interpretación, ayuda en español y su pequeño tamaño...(AU)

The practical use of Biostatistics is a concern for any researcher. Four tools were created aimed at providing the mathematical calculation of the statistical tests used in epidemiological researches as well as its application and interpretation, these tools use a free software, without property OpenOffice.org.Calc 2.3 of the Unix Ubuntu 8.04 of Linux operative system (with a copy in Microsoft Office Excel to its generalization) having the title of: “Pilotos statistics. A digital-educational statistical package for the epidemiological researches” in Pinar del Rio during 2008. The software contains 18 statistical tests; chi square test (includes Yatess correction), Fishers test of exact probability, odds ratio, relative risk, attributable risk percent and Kappas and Youdens rates, dependent tests a-b-c-d of contingency table 2x2. Besides; the calculation of the mean, standard deviation, variance, Z statistic and Mc Nemars chi square test. The tools were validated by means of professional programs and generalized in the final researches of the medical specialties, masters degree and other researches of the province. The tools were presented in provincial, national events and in South Africa (2007) and they are fundamental topics in postgraduate courses of Applied Biostatistics to the tutor, without the substitution of the professional syllabuses; the tools are added to easier the acquisition of knowledge in Biostatistics. The most important advantages of these tools are: the simplicity, applicability and immediacy, as well as the results in unison, easy interpretation, help in Spanish language and little size...(AU)

Questões em bioestatística: algumas reflexões sobre a comparação de médias / Biostatistical questions: some reflections on the comparison of means

O presente artigo analisa criticamente os usos e abusos dos testes estatísticos de comparação entre médias, bem como sugere novos enfoques metodológicos para a coleta e análise de dados objetivando alcançar resultados mais fidedignos.

This paper critically examines the uses and abuses of statistical tests to compare means, and suggests new methodological approaches to collect and analyze data in order to achieve more reliable results.