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Background & objectives: Due to lack of appropriate statistical knowledge, published research articles contain various errors related to the design, analysis and interpretation of results in the area of biomedical research. If research contains statistical error, however, costly, it may be of no use and the purpose of the investigation gets defeated. Many biomedical research articles published in different peer reviewed journals may retain several statistical errors and flaws in them. This study aimed to examine the trend and status of application of statistics in biomedical research articles. Study design, sample size estimation and statistical measures are crucial components of a study. These points were evaluated in published original research articles to understand the use or misuse of statistical tools. Methods: Three hundred original research articles from the latest issues of selected 37 journals were reviewed. These journals were from the five internationally recognized publication groups (CLINICAL KEY, BMJ Group, WILEY, CAMBRIDGE and OXFORD) accessible through the online library of SGPGI, Lucknow, India. Results: Among articles assessed under present investigation, 85.3 per cent (n=256) were observational, and 14.7 per cent (n=44) were interventional studies. In 93 per cent (n=279) of research articles, sample size estimation was not reproducible. The simple random sampling was encountered rarely in biomedical studies even though none of the articles was adjusted by design effect and, only five articles had used randomized test. The testing of assumption of normality was mentioned in only four studies before applying parametric tests. Interpretation & conclusions: In order to present biomedical research results with reliable and precise estimates based on data, the role of engaging statistical experts need to be appreciated. Journals must have standard rules for reporting study design, sample size and data analysis tools. Careful attention is needed while applying any statistical procedure as, it will not only help readers to trust in the published articles, but also rely on the inferences the published articles draw.
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PURPOSE: Use of inappropriate statistical methods may lead to incorrect conclusions and a waste of valuable resources. The goal of this study was to assess the frequency and the types of several common statistical errors in the published articles of the Journal of the Korean Academy of Prosthodontics (JKAP) for a 5-year period. MATERIALS AND METHODS: Of 336 articles in the JKAP published from 2006 to 2010, 255 articles using statistics were reviewed and classified by statistical method and year. The frequency and types of the statistical methods were examined, and the statistical errors were evaluated by the appropriateness of the experimental design, assumption check, independent outcomes, proper sample size and suitable use of statistical method. Statistical guidelines were completed based on the appropriateness. RESULTS: Of the 255 articles using statistics, 193 articles (75.9%) used inferential statistics and 153 articles used SPSS statistical software (60.0%). Of the articles using inferential statistics, the three most frequently used statistical methods were ANOVA (41.5%), t-test (20.0%), and the nonparametric method (16.9%). The average rate of statistical errors was 61.2 percent, similar to the rate reported by several studies completed for the medical journal. CONCLUSION: After the whole analysis of the difference among the groups, post-hoc tests for the pairwise comparisons are required. The optimal sample size calculation is an essential part of this study protocol. To minimize the occurrence of statistical errors, statistical guidelines were developed according to each statistical test procedure and will contribute to the academic improvement in the JKAP.
Subject(s)
Prosthodontics , Research Design , Sample SizeABSTRACT
Statistical analysis is an essential component of all biomedical research. Use of descriptive and inferential analysis enables researchers to summarize findings and conduct generalizations from research findings. Physicians must keep current with clinical information to practice evidence-based medicine. In doing so, physicians need to access reports of original research. This requires the reader to critically appraise the design, conduct, and analysis of each study and subsequently interpret the results. However, many surveys reveal prevalent statistical errors in articles in medical journals, and it is also clear that many physicians are seriously unfamiliar with statistical methods. This constitutes a major barrier to the development of medical research. Given this situation, this review article discusses the use of statistical methods in medical journal articles, the status of statistical errors among them, and the results of evaluation of physicians' understanding of statistical methods. Moreover, this article introduces the current trend in statistical reviews to improve the quality of medical journal articles, and explains the uniform requirements for manuscripts submitted to medical journals. Finally, the article proposes several specific ways to improve the quality of the Pediatric Allergy and Respiratory Disease.
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Evidence-Based Medicine , Generalization, Psychological , Hypersensitivity , Quality ImprovementABSTRACT
STATEMENT OF PROBLEM: The aim of dental research is to advance scientific knowledge and leads to improvement in the treatment and prevention of dental disease. Utilizing an effective research design and adequate statistical methods are essential procedures ensuring that the results of researches are based on evidences. A research should utilize proper statistical methods without statistical errors; Otherwise, it could adversely affect clinical practice and future research. PURPOSE: This study was made to investigate the statistical methods used in the Journal of Korean Academy of Prosthodontics (JKAP) and then to assess them for the statistical errors. MATERIAL AND METHODS: Among the total of 399 articles in the JKAP published from 2000 to 2006, 292 articles using statistics were reviewed. The validity of the statistical methods used in them were assessed using a checklist based on the guideline for statistical reporting in the uniform requirements for manuscripts submitted to biomedical journals by International Committee of Medical Journal Editors. The checklist consisted of three categories of statistical errors: 1) Unspecified computer statistical packages, 2) Inadequate description of statistical methods, 3) Misuse of statistical terms. Then, the results were compared between the Korean version and the English version in the JKAP. RESULTS: Among the 212 articles using statistics in the Korean version, 115 articles (54%) and among the 80 articles using statistics in the English version, 47 articles (59%) were shown to have unspecified computer statistical packages without statistically significant difference (P = .66). Likewise, 101 articles (48%) in the Korean version and 25 articles (31%) in the English version were shown to have the inadequate description of statistical methods without statistically significant difference (P = .09). However, 114 articles (54%) in the Korean version and 19 articles (24%) in the English version were shown to have the misuse of statistical terms with statistically significant difference (P = .01). CONCLUSION: Some of the articles in the JKAP had inadequate statistical validity, given the statistical errors identified in this assessment. Hence, dental researchers should be more careful when it comes to describing and applying statistical methods.
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Checklist , Dental Research , Prosthodontics , Research Design , Stomatognathic DiseasesABSTRACT
PURPOSE: The purpose of this study was to assess the statistical methods used in the Journal of the Korean Society of Emergency Medicine (JKSEM) and to identify the types of errors in statistical analysis. METHODS: We reviewed quantitative articles that were published in the JKSEM from January 1998 through December 2002. Editorials, review articles, and case reports were not included in this analysis. A total of 319 articles was reviewed. We focused on the methods of inferential statistics in these articles. We evaluated the adequacy and the validity of the statistical techniques with our criteria, which were established by modifying Ahn's checklist. RESULTS: Of the 319 articles, 222 used inferential statistics. The t-test was the statistic of choice overall (45.1%), followed by the chi-square test (23.9%). Errors of omission (70.3%) were more frequent than errors of commission. Of the errors of omission, incomplete description of the basic data was the most common. CONCLUSION: We found various mistakes or misuses in the applications of statistical methodologies in the articles published in the JKSEM. The present study suggests that additional efforts should be focused on the appropriateness of the statistical analysis used in JKSEM articles to improve their value, and during the review process, editorial attention should be paid to the validity of the statistical methodologies used in the articles.
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Checklist , Emergencies , Emergency MedicineABSTRACT
The statistical analysis is an essential procedure ensuring that the results of researches are based on evidences rather than opinion. The purpose of this study is to evaluate the statistical methods and errors in JKPRS and to propose improvement plan.We reviewed 326 articles published in JKPRS between 1996 and 1999. We evaluated the validity of used statistical methodology with our own checklist based on "Guideline for statistical reporting in articles for medical journals" by "International committee of medical journal editors". Among 326 articles, case(series) report and original articles were 167(51.2%) and 156(47.9%) respectively. In 159(48.8%) papers statistical method was not used. In 94 (28.8%) papers, only descriptive methods were used, while in 73 papers(22.4%) descriptive and inferential methods were used. The papers published in 1999 used more statistical methods than in 1996. Among the papers which used descriptive method, 90 papers(53.0%) showed appropriate central tendency and dispersion. But, in papers which used inferential method, 24 papers(33.0%) applied appropriate methods and only 4 papers(5.5%) were satisfactory in utilization of statistical methodology. It is suggested that more consultation of investigators with bio-statisticians, a basic training on statistical methods in resident programs, and more extensive statistical refereeing are needed.
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Humans , Checklist , Research PersonnelABSTRACT
BACKGROUND: The Korean Journal of Anesthesiology (KJA) was first published in 1968 containing only 16 articles. In 1998, the number is 291. However, the quantitative growth does not mean a qualitative growth. There are many aspects to improving quality. One of them is statistical accuracy. I have examined the statistical methods in our field and checked the accuracy of the methods. Then, I compared the results with the methods in the 1980s and examined what kinds of changes exist. METHODS: I reviewed all the articles except case reports and review articles in KJA published from 1994 to 1998. I focused on the methods of inferential statistics because those kinds of statistics were usually mentioned in the articles. It is based on the mentioned technique in the article to decide which inferential statistics are used, even though sometimes they are not accurate. I adopted the similar statistical error criteria selected by Ko. RESULTS: Basic statistical error, for example no statistics used even though statistical methods are needed, were dramatically reduced compared to the 1980s. It is increased to use the mean comparison methods correctly, but, some statistical methods are still misused frequently, for example Chi-square test, nonparametric analysis, multiple comparison methods and improperly adopted methods based on the variable scale. CONCLUSION: Generally, based on my criteria statistical errors are reduced from about 75% in the 1980s to about 60% in the 1990s.