Is the Bland-Altman plot method useful without inferences for accuracy, precision, and agreement?

ABSTRACT OBJECTIVE This study aims to propose a comprehensive alternative to the Bland-Altman plot method, addressing its limitations and providing a statistical framework for evaluating the equivalences of measurement techniques. This involves introducing an innovative three-step approach for assessing accuracy, precision, and agreement between techniques, which enhances objectivity in equivalence assessment. Additionally, the development of an R package that is easy to use enables researchers to efficiently analyze and interpret technique equivalences. METHODS Inferential statistics support for equivalence between measurement techniques was proposed in three nested tests. These were based on structural regressions with the goal to assess the equivalence of structural means (accuracy), the equivalence of structural variances (precision), and concordance with the structural bisector line (agreement in measurements obtained from the same subject), using analytical methods and robust approach by bootstrapping. To promote better understanding, graphical outputs following Bland and Altman's principles were also implemented. RESULTS The performance of this method was shown and confronted by five data sets from previously published articles that used Bland and Altman's method. One case demonstrated strict equivalence, three cases showed partial equivalence, and one showed poor equivalence. The developed R package containing open codes and data are available for free and with installation instructions at Harvard Dataverse at https://doi.org/10.7910/DVN/AGJPZH. CONCLUSION Although easy to communicate, the widely cited and applied Bland and Altman plot method is often misinterpreted, since it lacks suitable inferential statistical support. Common alternatives, such as Pearson's correlation or ordinal least-square linear regression, also fail to locate the weakness of each measurement technique. It may be possible to test whether two techniques have full equivalence by preserving graphical communication, in accordance with Bland and Altman's principles, but also adding robust and suitable inferential statistics. Decomposing equivalence into three features (accuracy, precision, and agreement) helps to locate the sources of the problem when fixing a new technique.

Sports injuries in high-level aerobic gymnastics athletes / Lesões esportivas em atletas de ginástica aeróbica de alto nível / Lesiones deportivas en atletas de gimnasia aeróbica de alto nivel

ABSTRACT Introduction: With the rapid development of aerobic gymnastics worldwide, research is required to constantly increase. Objective: Analyze the main causes of sports injuries, proposing measures for prevention, treatment, and rehabilitation, as well as providing a theoretical basis for reducing the risk of sports injuries and actively seeking ways and measures to prevent and treat sports injuries in aerobic gymnastics athletes. Methods: Statistical-mathematical analysis was used, mainly including the coefficient of variation method, correlation matrix method, and factor analysis. The common variable of the trend of sports injuries was found. Results: The research shows that the scientific awareness, self-protection, and injury prevention of aerobic gymnastics training strengthen the ideological education and theoretical guidance of athletes, improve athletes' awareness of sports injuries, regulate technical specifications, strengthen fitness training and improve Chinese competitive aerobics. Conclusion: In the healthy period before injuries, we should take various measures to improve physical fitness and skills, enabling good health work in the acute period after injuries and understanding the working principle of early diagnosis and treatment to better use treatment time. Level of evidence II; Therapeutic studies - investigation of treatment outcomes.

RESUMO Introdução: Com o rápido desenvolvimento da ginástica aeróbica no mundo, é requisitado o aumento no nível das pesquisas constantemente. Objeto: Analisar as principais causas de lesões esportivas, propondo medidas de prevenção, tratamento e reabilitação, além de fornecer uma base teórica para reduzir o risco de lesões esportivas e buscar ativamente formas e medidas para prevenir e tratar lesões esportivas em atletas de ginástica aeróbica. Métodos: Foi utilizada uma análise estatística-matemática, principalmente incluindo o método de coeficiente de variação, método de matriz de correlação e análise de fatores. Encontrou-se a variável comum da tendência das lesões esportivas. Resultados: A pesquisa mostra que a consciência científica, autoproteção e prevenção de lesões dos métodos de treinamento de ginástica aeróbica fortalece a educação ideológica e a orientação teórica dos atletas, melhora a consciência dos atletas sobre lesões esportivas, regula especificações técnicas, fortalece o treinamento de aptidão física e melhora a aeróbica competitiva chinesa. Conclusão: No período saudável antes das lesões, devemos tomar várias medidas para aprimorar a aptidão física e as habilidades, permitindo um bom trabalho de saúde no período agudo após as lesões, compreendendo o princípio de trabalho de diagnóstico e tratamento precoces para aproveitar melhor o tempo de tratamento. Nível de evidência II; Estudos terapêuticos - investigação dos resultados do tratamento.

RESUMEN Introducción: Con el rápido desarrollo de la gimnasia aeróbica en el mundo, es necesario aumentar constantemente el nivel de investigación. Objetivo: Analizar las principales causas de las lesiones deportivas, proponiendo medidas de prevención, tratamiento y rehabilitación, así como proporcionar una base teórica para reducir el riesgo de lesiones deportivas y buscar activamente formas y medidas para prevenir y tratar las lesiones deportivas en los deportistas de gimnasia aeróbica. Métodos: Se utilizó el análisis estadístico-matemático, que incluye principalmente el método del coeficiente de variación, el método de la matriz de correlación y el análisis factorial. Se encontró la variable común de la tendencia de las lesiones deportivas. Resultados: La investigación muestra que la concienciación científica, la autoprotección y la prevención de lesiones de los métodos de entrenamiento de la gimnasia aeróbica refuerzan la educación ideológica y la orientación teórica de los atletas, mejoran la concienciación de los atletas sobre las lesiones deportivas, regulan las especificaciones técnicas, refuerzan el entrenamiento físico y mejoran el aeróbic de competición chino. Conclusión: En el período de salud antes de la lesión, debemos tomar varias medidas para mejorar la aptitud física y las habilidades, lo que permite un buen trabajo de salud en el período agudo después de la lesión, la comprensión del principio de trabajo de diagnóstico y tratamiento temprano para hacer un mejor uso del tiempo de tratamiento. Nivel de evidencia II; Estudios terapéuticos - investigación de los resultados del tratamiento.

Significancia Estadística en Ciencias de la Salud: Limitaciones y Alternativas / Statistical significance in the field of health sciences: limitations and alternatives

Introducción. La prueba de significancia de la hipótesis nula (PSHN) constituye la herramienta más usada para evaluar hipótesis científicas y tomar decisiones al respecto, en especial en ciencias de la salud. Sin embargo, por décadas ha estado en el centro del debate, ya que se han identificado varios problemas conceptuales y de interpretación. Se realizó una revisión de artículos científicos que ilustran las críticas de esta controversia y su relevancia en el ámbito de la investigación en salud. Algunas alternativas para la PSHN son una adecuada interpretación del valor p, uso de intervalos de confianza, incluir el tamaño del efecto y adoptar un marco de inferencia bayesiana. En todos los casos en que se utilice PSHN, su uso debe ser claramente justificado.

Background. Null hypothesis significance testing (NSHT) constitutes the most widely applied tool for the evaluation of scientific hypotheses and decision making in health sciences. However, the method has been the centre of a heated debate where various criticisms related to conceptual and interpretational problems. A review of scientific articles that illustrate the criticisms of this controversy and its relevance in the field of health research was carried out. Some alternatives for the NSHT are an adequate interpretation of the p-value, use of confidence intervals, including the effect size and adopting a Bayesian inference framework. In all cases where NSHT is used, its use should be clearly justified.

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)

Estadística inferencial en la actividad científica de la residencia de Medicina General Integral en Artemisa / Inferential statistics in the scientific activity of Family Medicine in Artemisa

Introducción: la objetividad de los resultados de las indagaciones que realizan los médicos de familia en su comunidad determina el nivel científico de las investigaciones que acontecen en la atención primaria de salud cubana. Objetivo: caracterizar el comportamiento del uso de las pruebas estadísticas de inferencia en la actividad científico-investigativa de la residencia de Medicina General Integral del policlínico docente Dr. Tomás Romay"del municipio Artemisa. Métodos: se realizó un estudio observacional analítico, se aplicó una guía de observación a los 29 trabajos de terminación de especialidad realizados durante los cursos académicos 2013-2014 hasta 2015-2016, donde se constataron los diferentes niveles alcanzados por los residentes durante la aplicación de pruebas estadísticas de inferencia para validar sus resultados de investigación. Resultados: los residentes estudiados manifestaron poca preferencia por el uso de las pruebas estadísticas de inferencia para la investigación, que en los casos favorables su utilización es arbitraria no acordes a los criterios establecidos para su selección y que existen grandes dificultades en el procedimiento lógico de su aplicación. El proceso formativo de Médicos de Familia en el municipio Artemisa presentó dificultades en el fortalecimiento del componente investigativo de sus residentes durante los cursos estudiados(AU)

Introduction: The objectiveness of results from research performed by family physicians in their communities determines the research-scientific level in primary healthcare in Cuba. Objective: To characterize the use of statistical inference tests in the research-scientific activity of the residency in Family Medicine at Dr. Tomás Romay Teaching Polyclinic in Artemisa. Methods: An observational, analytical study was carried out. An observation guide was applied to the 29 final works for the specialty submitted during the academic years 2013-2014 and until 2015-2016, where we clearly perceived the different levels reached by residents during the application of statistical inference tests to validate their research results. Results: The residents studied showed little preference for the use of statistical inference tests for research. In the favorable cases their use is arbitrary, not in accordance with the criteria established for such selection, while there are great difficulties in the logical procedure of their application. The training process of family physicians in Artemisa Municipality presented difficulties in strengthening the research component of its residents during the courses studied(AU)

Las pruebas de significación estadística: seis décadas de fuegos artificiales / Tests of statistical significance: six decades of fireworks / As provas de significação estatística: seis décadas de fogos artificiais

RESUMEN Tras varios decenios de críticas a las técnicas inferenciales basadas en las pruebas de significación estadística orientadas al rechazo de la llamada "hipótesis nula" y, a pesar del notable consenso alcanzado entre los estadísticos profesionales, este recurso se mantiene vigente tanto en las publicaciones biomédicas, entre ellas las de Salud Pública, como en cursos introductorios de estadística. Entre las muchas deficiencias señaladas por los más prominentes especialistas se destacan tres por ser las más obvias y fáciles de comprender: que no contribuyen a cumplimentar la encomienda de la ciencia, que se conocen de antemano las respuestas a las preguntas que se encaran por su conducto y que los resultados que producen dependen de un elemento ajeno a la realidad estudiada: el tamaño muestral. El artículo discute en detalle tales limitaciones, ilustra su perniciosa presencia en la investigación actual y valora las razones para la subsistencia de la sinrazón en esta materia.

ABSTRACT After decades of criticism against inferential techniques based on statistical significance tests, which mainly reject the so-called "null hypothesis", and in spite of the remarkable consensus among professional statisticians, this resource remains prevalent in both biomedical publications (including public health journals) and introductory statistics courses. Among the many problems identified by the most prominent specialists, three of them are the most obvious and easy to understand: that these tests do not contribute to the actual enterprise of science, that the answers to the questions that are addressed are known in advance and that their results depend critically on an element that is external to the domain that is being studied: sample size. This paper discusses in detail these limitations, illustrates their pernicious presence in current research and evaluates the reasons for the survival of the senselessness in this matter.

RESUMO Trás vários decênios de críticas as técnicas inferenciais baseadas nas provas de significação estatística orientadas ao rejeito da chamada "hipótese nula" e, embora do notável consenso alcançado entre os estatísticos profissionais, este recurso se mantem vigente tanto nas publicações biomédicas, entre elas as de Saúde Pública, como nos cursos introdutórios de estatística. Entre as muitas deficiências assinaladas pelos mais proeminentes especialistas se destacam três por ser as mais obvias e fácies de compreender: que não contribuem a complementar a encomenda da ciência, que se conhecem de antemão as respostas ás perguntas que se encaram pelo seu conduto y que os resultados que produzem depende dum elemento alheio á realidade estudada: o tamanho amostral. O artigo discute em detalhe tais limitações, ilustra a sua perniciosa presença na investigação atual e valora as razões para a subsistência da sem-razão em esta matéria.

Probability sampling design in ethnobotanical surveys of medicinal plants

Non-probability sampling design can be used in ethnobotanical surveys of medicinal plants. However, this method does not allow statistical inferences to be made from the data generated. The aim of this paper is to present a probability sampling design that is applicable in ethnobotanical studies of medicinal plants. The sampling design employed in the research titled "Ethnobotanical knowledge of medicinal plants used by traditional communities of Nossa Senhora Aparecida do Chumbo district (NSACD), Poconé, Mato Grosso, Brazil" was used as a case study. Probability sampling methods (simple random and stratified sampling) were used in this study. In order to determine the sample size, the following data were considered: population size (N) of 1179 families; confidence coefficient, 95%; sample error (d), 0.05; and a proportion (p), 0.5. The application of this sampling method resulted in a sample size (n) of at least 290 families in the district. The present study concludes that probability sampling methods necessarily have to be employed in ethnobotanical studies of medicinal plants, particularly where statistical inferences have to be made using data obtained. This can be achieved by applying different existing probability sampling methods, or better still, a combination of such methods.