Reporting of Basic Statistical Methods in Biomedical Journals: Improved SAMPL Guidelines

Statistical methods have become an essential component of all empirical biomedical research. Science requires that these methods arefully reported with complete accuracy so that the evidence base could be fully appraised for validity, reliability, and generalizability. Tomeet this objective, Statistical Analyses and Methods in Published Literature (SAMPL) guidelines have been prepared for statisticalreporting in biomedical publications. This communication proposes substantial improvement of these guidelines to make them morecomprehensive, organized, compact, and easier to adopt.

Elementos para evitar errores en el diseño de investigaciones en ciencias de la salud / Elements to avoid mistakes in the design of research in health sciences

La Estadística y el rigor metodológico deben guiar una investigación en todo su desarrollo para asegurar la coherencia investigativa; el desconocimiento y el uso incorrecto de las herramientas estadísticas y metodológicas se traduce en investigaciones con discutible validez interna, reflejada en errores. En este artículo se revisan los elementos necesarios para evitar errores metodológicos y estadísticos en la fase del diseño de una investigación en el contexto de las ciencias de la salud. Se abordan los diferentes tópicos con un enfoque crítico y haciendo uso de diversos ejemplos de investigaciones reales. Una vez planteado correctamente un problema de investigación debe elegirse el diseño que esté más protegido de posibles sesgos; el muestreo debe asegurar la representatividad y adecuación en tamaño de la muestra, así como la definición precisa de criterios de selección. Para aplicar una herramienta estadística deben evaluarse: el tipo y escala de las variables dependientes e independientes, la cantidad y grado de independencia de los grupos de comparación, el alcance y tipo de investigación, entre otros.

Statistics and methodological rigor should guide a research in the whole process in order to assure the research coherence. The lack of knowledge and the appropriate use of statistical a methodological tools becomes to researches with doubts about internal validity, showed in systematic mistakes and other kind of mistakes. In this article needed elements were systematically examined to avoid these mistakes especially in the design phase of a research, talking in the context of health sciences. These topics were focused in critical form and using several examples of real researches. Once a research problem is correctly set, a design will be chose, the one that is most protected of possible bias. The sampling must assure the representativeness and appropriateness of the sample size, as well as an accurate definition of selection criteria. To apply a statistical tool it is necessary to evaluate: the type and scale of dependent and independent variables, quantity and rate of independence of comparison groups, extent and research type, among others

Necesidad de fortalecer el arbitraje de los informes de investigación enviados a la Gaceta Médica Espirituana / The need for strengthening the arbitration of the reports of investigation sent to the Medical Gazette of Sancti Spiritus

La Estadística es ampliamente utilizada por los profesionales de las ciencias médicas no solo como recurso auxiliar en el enfrentamiento y solución a problemas de su profesión que contribuye a valorar y tomar decisiones sobre los diseños de investigación, sino también para mantener actualizados sus conocimientos mediante la lectura crítica de las evidencias provenientes de la investigación científica, así como para comunicarse con otros profesionales a propósito del análisis de sus datos.

Statistics is widely used by the professionals of the Medical Sciences, not only as a an auxiliary tool but also to face and give solution to the problems of their field which contribute to the assessment and decision taken about designs of investigation, moreover to keep updated by critical reading of evidences coming from the scientific investigation, besides to communicate with other professionals with the purpose of analyzing their data.

Avoiding negative reviewer comments: common statistical errors in anesthesia journals / 대한마취과학회지

Manuscripts submitted to journals should be understandable even to those who are not experts in a particular field. Moreover, they should use publicly available materials and the results should be verifiable and reproducible. Readers and reviewers will want to check the strengths and weaknesses of the research study design, and ways to make this determination should be clear through proper analysis methods. Studies should be described in detail so as to help readers understand the results. Statistical analysis is one of the key methods by which to do this. The inappropriate application of statistical methods could be misleading to readers and clinicians. While many researchers describe their general research methods in detail, statistical methods tend to be described briefly, with certain omissions or errors or other incorrect aspects. For instance, researchers should describe whether the median or mean was used, whether parametric or nonparametric tests were used, whether the data meet the normality test, whether confounding factors were corrected, and whether stratification or matching methods were used. Statistical analysis regardless of the program should be reported correctly. The results may be less reliable if the statistical assumptions before applying the statistical method are not met. These common errors in statistical methods originate from the researcher's lack of knowledge of statistics and/or from the lack of any statistical consultation. The aim of this work is to help researchers know what is important statistically and how to present it in papers.

Use and Misuse of Statistical Methods in the Journal of Korean Academy of Nursing Administration / 간호행정학회지

PURPOSE: To do nursing research effectively requires an understanding of fundamental principles of statistical methods. In this article, some key statistical methods which are commonly used in nursing research are identified and summarized. METHODS: Ninety-two original articles from the Journal of Korean Academy of Nursing Administration were reviewed. Statistical methods were classified and summarized for usage in research and occurrence of common errors. RESULTS: Among the original articles reviewed, 58 statistical usages contained errors. Most errors were found in linear regression analysis, Pearson correlation analysis, and chi-square test. From the detection of statistical errors in usage, suggestions for appropriate statistical methods were made. CONCLUSION: In order to improve validity of original articles in the Journal of Korean Academy of Nursing Administration, clearly stated statistical usage and close editorial attention to statistical methods are needed. Understanding statistical methods is part of the process that researchers must use to determine both quality and usefulness of the research. Research findings will be used to guide nursing practice and reduce uncertainty in decision making. However, to understand how to interpret research results, it is important to be able to understand basic statistical concepts. Researchers should also choose statistical methods that match their purposes.

Analysis on common statistical error in articles about acupuncture and moxibustion / 中华中医药杂志

Science of acupuncture and moxibustion is an important component of traditional Chinese medicine.There are many statistical errors in articles about acupuncture and moxibustion in recently years.In order to enhancing the level of writing on articles about acupuncture and moxibustion,this article analyzed the common statistical error in articles about acupuncture and moxibustion in national core journals in the past three years,and gave a solution to the problem.

An Evaluation of the Statistical Techniques used in the 1994~1998 Editions of The Journal of the Korean Rheumatism Association / 대한류마티스학회지

OBJECTIVE: Quantitative experiment and analysis of the result with statistical techniques are an essential part of the medical article for acquiring objective confidence. But errors on application, calculation, and interpretation of statistics and insufficient explanation of the used statistical technique deprive the reader of reliance on the article. We identified the statistical techniques and errors that were commonly encountered, and both of researchers and readers should recognize, in the Journal of the Korean Rheumatism Association (JKRA). We identified the frequency of the statistical techniques and errors from the 136 articles in the 1994~1998 editions of the JKRA. Each different kind of statistical techniques and errors in the same article were counted separately, but two or more of the same kind of statistical techniques and errors in an article were counted as one. One hundred and seventy-seven statistical techniques were encountered and 75 statistical errors were identified. The most frequently used techniques were descriptive statistics, and common errors and the observed numbers of the errors were as follow : 1. performing statistical techniques for two groups on the comparison of three or more groups(14), 2. mentioning the statistical technique without using it(14), 3. using mean and standard deviation instead of median and range on the ordinal data(12), 4. using standard error instead of standard deviation for the description of data spread(11), 5. using p value without the statistical name(11). CONCLUSION: The most frequently encountered statistical technique and error are descriptive technique and performing statistical techniques for 2 groups on the comparison of 3 or more groups, respectively. The authors? careful application of the basic statistics would be the real solution to reduce the statistical errors.

An Evaluation of the Statistical Techniques used in the 1995-1996 editions of the Korean Journal of Clinical Pathology / 대한임상병리학회지

BACKGROUND: Quantitative experiment and analysis of the result with statistical techniques are an essential part of the medical article for acquiring objective confidence. But errors on application, calculation, and interpretation of statistics and insufficient explanation of the used statistical technique deprive the reader of reliance on the article. We identified the statistical errors that were commonly encountered and which researchers and readers should recognize in the Korean Journal of Clinical Pathology (KJCP) in order to improve the quality of the statistics in the article. METHODS: We identified the frequency of the statistical errors from the 193 articles in the 1995 - 1996 editions of the KJCP. There were seven kinds of statistical errors that were most frequently observed. Each different kind of error in the same article were counted separately, but two or more of the same kind of error in an article were counted as one. RESULTS: Seventy-five statistical errors were identified. Seven kind of the most common errors and the observed numbers of the every kind of error were as follow : 1. Using P value without the statistical name (12), 2. Performing t test instead of the analysis of variance (ANOVA) test in comparing the means of three or more groups (11), 3. Omitting the F test on the unpaired t test in small different sized samples (10), 4. Mentioning the statistical technique without using it (9), 5. Mentioning the predictive value without prevalence (7), 6. Not performing multiple comparison after the significant ANOVA test (5), 7. Not using the P value with the correlation coefficient (r) (5). CONCLUSIONS: There were 75 statistical errors in the 1995-1996 editions of the KJCP. Not mentioning the name of the statistical technique used was the most frequently observed error. The authors' careful application of the basic statistics would be the real solution of the problem.

Statistical Errors in Papers in the two Korean Dermatology Journals

BACKGROUND: Statistical errors have been noted in a large percentage of articles appearing in medical journals. Their incidence in the Annals of Dermatology and the Korean Journal of Dermatology, however, has not been studied. OBJECTIVE: The purpose of this study was to evaluate the accuracy of statistical methods in the Annals of Dermatology and the Korean Journal of Dermatology. METHOD: Original papers using the t test in the Annals of Dermatology(AD) and in the Korean Journal of Dermatology(KJD) from January 1990 to July 1994 were analyzed for correctness of statistical methods. RESULTS: Of the 376 original papers in the period considered, 78(20.7%) presented t tests and 43(55.1%) of these also contained some errors. Of the 9 papers from the Annals of Dermatology, 4(44.4%) included at least one error. Of the 69 papers from the Korean Journal of Dermatology, 39(56.5%) included at least one error. CONCLUSION: Misuse of statistical methodology may not be uncommon in the two Korean Dermatology journals, and it would be prudent to give more attention to statistical methodology.