• Journal of Periodontal and Implant Science
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• v.44 no.6
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• pp.288-292
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• 2014

Purpose: The purposes of this study were to assess the trend of use of statistical methods including parametric and nonparametric methods and to evaluate the use of complex statistical methodology in recent periodontal studies. Methods: This study analyzed 123 articles published in the Journal of Periodontal & Implant Science (JPIS) between 2010 and 2014. Frequencies and percentages were calculated according to the number of statistical methods used, the type of statistical method applied, and the type of statistical software used. Results: Most of the published articles considered (64.4%) used statistical methods. Since 2011, the percentage of JPIS articles using statistics has increased. On the basis of multiple counting, we found that the percentage of studies in JPIS using parametric methods was 61.1%. Further, complex statistical methods were applied in only 6 of the published studies (5.0%), and nonparametric statistical methods were applied in 77 of the published studies (38.9% of a total of 198 studies considered). Conclusions: We found an increasing trend towards the application of statistical methods and nonparametric methods in recent periodontal studies and thus, concluded that increased use of complex statistical methodology might be preferred by the researchers in the fields of study covered by JPIS.

• The Journal of Korean Academy of Prosthodontics
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• v.47 no.3
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• pp.273-285
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• 2009

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.

• Proceedings of the Korean Environmental Health Society Conference
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• 2002.04a
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• pp.52-54
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• 2002

Generally, inaccurate reports on environmental issues occur due to various factors. The purpose of this study was to find out a way to enhance accuracy of environmental reporting. So the reporters' career and college major had been compared to the accuracy of their articles. The by-lined environmental articles in nine dailies published in 1991 were checked. Results of this study were as follows. (1) Inaccuracy rate in environmental articles was 54.2％. Inaccuracies appeared 1.7 times per an article, while the average frequency of inaccuracies in overall articles was 0.9 time. (2) Errors in the articles consist of 65.8％ of subjective inaccuracies and 34.2％ of subjective inaccuracies. They derive from the false usage of terminology(15.8％), misquotation(14.5％), incorrect statistics(13％), exaggeration(13％), inaccurate title(7.9％), and false comparison(5％), (3) Inaccuracy rate by the type of articles was 66.7％ in columns, 60％ in feature stories, 54.5％ in-depth stories, 40.9％ in straight news, respectively. (4) Inaccuracy rate by the specific field was shown 71.4％ in environmental impacts (5) According to the result of chi-square test analysis, there were no statistically significant differences of inaccuracy rate and of subjective, and objective, and objective inaccuracies relevant to the period of reporters' career covering environmental reporting and the nature of articles, and college major.

• Journal of Environmental Health Sciences
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• v.28 no.1
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• pp.31-39
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• 2002

Generally, inaccurate reports on environmental issues occur due to various factors. The purpose of this study was to find out a way to enhance accuracy of environmental reporting. So the reporters' career and college major had been compared to the accuracy of their articles. The by-lined environmental articles in nine dailies published in 1991 were checked. Results of this study were as follows. (I) Inaccuracy rate in environmental articles was 54.2%. Inaccuracies appeared 1.7 times per an article, while the average frequency of inaccuracies in overall articles was 0.9 time. (2) Errors in the articles consist of 65.8% of subjective inaccuracies and 34.2% of subjective inaccuracies. They derive from the false usage of terminology(15.8% ),misquotation(14.5%), incorrect statistics(13%), exaggeration(13%), inaccurate title(7.9%), and false comparison(5%). (3) Inaccuracy rate by the type of articles was 66.7% in columns, 60% in feature stories, 54.5% in-depth stories, 40.9% in straight news, respectively. (4) Inaccuracy rate by the specific field was shown 71.4% in environmental impacts assessment, 52.5% in water pollution, 37.5% in waste management, and 35.7% in air pollution. (5) According to the result of chi-square test analysis, there were no statistically significant differences of inaccuracy rate and of subjective, and objective inaccuracies relevant to the period of reporters' career covering environmental reporting and the nature of articles, and college major.

• Journal of Society of Preventive Korean Medicine
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• v.15 no.1
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• pp.17-27
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• 2011

Objective : The purpose of this study was to identify the trend of research in the Korean Journal of Oriental Preventive Medicine and to suggest future perspective for oriental preventive medicine research. Method : The contents of 344 articles published in this journal was reviewed from its beginning year 1997 to year 2010. Result : The number of articles was increased as times go on. An analysis of the research design showed, experimental research (in vivo or in vitro) was 36.9%, survey research was 26.5%, review was 20.1%. In the major classifications of topics published, health management 28.5%, oriental medicine effectiveness 25.3%, herbal safety and toxicity 13.1%, and environmental and occupational medicine 9.0% respectively. Conclusion : There has been a lack of health preservation(Yang-saeng) topic, epidemiology and health statistics topic. Further research need qualitative study and each subjects of oriental preventive medicine.

• The Journal of Korean Academy of Prosthodontics
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• v.50 no.4
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• pp.258-270
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• 2012

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.

• Herbal Formula Science
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• v.18 no.1
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• pp.57-77
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• 2010

Objective : This study reviews the recent trend of oriental medical prescription research. The data examined are the articles published in the Korean Journal of Oriental Medical Prescription from 1990 to 2009. Method : The data are retrieved through the internet database Oriental Medicine Advanced Searching Integrated System (OASIS) and the collection of the Korean Journal of Oriental Medical Prescription. The number of articles examined is 385, published in 25 volumes of the journal. This study examines the nature of the articles, research methods, subjects, and author information. Research subjects are sorted out by the OASIS key words for the articles published before 1999, and by key word indexes cited in the abstracts for the articles published sinceafter. Results : Among the 385 articles collected, 206 are research articles, 143 philological articles, 35 case studies, and 1 special contribution. A majority of research articles are experimental studies (199 articles or 96.6%), while clinical reports (5 articles or 2.43%), and others studies (2 articles) occupy a small portion. Most of experimental studies (183 articles or 91%) examine the effectiveness of certain prescriptions or treatments. Among the effectiveness studies, 114 articles (62.3%) employ in vivo experiment design, 52 articles (28.42%) in vitro experiments, and 17 articles (9.29%) both in vivo and in vitro experiments. In terms of research subject, the most frequently indexed key words are hepatotoxicity among diseases (9 articles), Bojungikgitang (Bu-Zhong-Yi-Qi-Tang) among prescriptions (10 articles), Buja (Acontii Tuber) among meteria medica (4 articles), immunity and anti-oxidation among efficacy terminology (6 articles each), and Donguibogam(東醫寶鑑) among references in the key words (25 articles). Universities are the main affiliation of authors (76.42%), followed by university hospitals (6.71%), non-academic research institutes (5.55%), local clinics (4.67), academic research institutes (2.81%), hospitals (2.38%), and others (1.44%). The most affiliated institute of the first and correspondent authors is Wonkwang University. In terms of authorship, co-authorship outnumbers sole-authorship by 82.08% to 17.92%. The proportion of authors of a single article is 63.54% which is near the author productivity distribution described by Lotka's law.

• Communications for Statistical Applications and Methods
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• v.28 no.6
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• pp.595-610
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• 2021

Recently a few articles have derived robust first-order rotatable and D-optimal designs for the lifetime response having distributions gamma, lognormal, Weibull, exponential assuming errors that are correlated with different correlation structures such as autocorrelated, intra-class, inter-class, tri-diagonal, compound symmetry. Practically, a first-order model is an adequate approximation to the true surface in a small region of the explanatory variables. A second-order model is always appropriate for an unknown region, or if there is any curvature in the system. The current article aims to extend the ideas of these articles for second-order models. Invariant (free of the above four distributions) robust (free of correlation parameter values) second-order rotatable designs have been derived for the intra-class and inter-class correlated error structures. Second-order rotatability conditions have been derived herein assuming the response follows non-normal distribution (any one of the above four distributions) and errors have a general correlated error structure. These conditions are further simplified under intra-class and inter-class correlated error structures, and second-order rotatable designs are developed under these two structures for the response having anyone of the above four distributions. It is derived herein that robust second-order rotatable designs depend on the respective error variance covariance structure but they are independent of the correlation parameter values, as well as the considered four response lifetime distributions.

• Journal of Korean Clinical Nursing Research
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• v.23 no.1
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• pp.73-82
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• 2017

Purpose: The aim of this study was to identify bibliographic characteristics and research trends of articles published in the Journal of Korean Clinical Nursing Research from 2009 to 2015. Methods: Descriptive statistics were used to analyze 268 articles. Bibliographic characteristics, appropriateness of methods for quantitative and qualitative studies, and key concepts of articles were analyzed. Results: A clinical nurse was the first author for 184 (66.7%) articles. The number of collaborative works between hospital and university was 184 (68.7%). Study participants were patients (120, 38.1%), nurses (115, 36.5%) and others. IRB approval was given for 156 articles (58.2%). Written informed consent was obtained in 125 articles (46.7%). Quantitative research accounted for 98.6% of the articles but qualitative studies only 4 (1.4%). Types of interventions in the experimental studies were nursing skills (43, 42.6%) and health education (32, 31.7%). Major keywords were nurses, pain, knowledge, intensive care unit, anxiety, depression, fatigue, and stress. Conclusion: Articles in this journal deal with topics and concepts confronted in nursing practice so experimental studies on applicability of nursing interventions were frequently published. Findings in this study indicate that the authors published in the journal contribute to the development of nursing with characteristics distinctive from other nursing journals published in Korea.

• Journal of the Korean Association of Oral and Maxillofacial Surgeons
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• v.44 no.1
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• pp.25-28
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• 2018

Objectives: This study aimed to describe recent patterns in the types of statistical test used in original articles that were published in Journal of the Korean Association of Oral and Maxillofacial Surgeons. Materials and Methods: Thirty-six original articles published in the Journal in 2015 and 2016 were ascertained. The type of statistical test was identified by one researcher. Descriptive statistics, such as frequency, rank, and proportion, were calculated. Graphical statistics, such as a histogram, were constructed to reveal the overall utilization pattern of statistical test types. Results: Twenty-two types of statistical test were used. Statistical test type was not reported in four original articles and classified as unclear in 5%. The four most frequently used statistical tests constituted 47% of the total tests and these were the chi-square test, Student's t-test, Fisher's exact test, and Mann-Whitney test in descending order. Regression models, such as the Cox proportional hazard model and multiple logistic regression to adjust for potential confounding variables, were used in only 6% of the studies. Normality tests, including the Kolmogorov-Smirnov test, Levene test, Shapiro-Wilk test, and $Scheff{\acute{e}}^{\prime}s$ test, were used diversely but in only 10% of the studies. Conclusion: A total of 22 statistical tests were identified, with four tests occupying almost half of the results. Adoption of a nonparametric test is recommended when the status of normality is vague. Adjustment for confounding variables should be pursued using a multiple regression model when the number of potential confounding variables is numerous.