This paper explains how to select the correct statistical test for a research project, clinical trial, or other investigation. It is important that the appropriate statistical analysis is decided upon before starting the study, at the stage of planning itself, to get correct analysis of data. This cannot be decided arbitrarily after the study is over and data has already been collected. Many studies have been rejected due to faulty selection of statistical test. The test to be used depends upon the type of research question being asked. The other determining factors are the type of data being analyzed and the number of groups or data sets involved in the study.

No abstract available.
Statistics as Topic*

Tissue array consists of a slide containing hundreds or thousands of cases, making this method useful for rapid analysis of molecular markers in a large number of cases. The method significantly facilitates and accelerates the clinicopathologic analysis of cancer. To maximize the efficacy of the tissue array method in pathologic study, the pros and cons of this method should be understood. In this review, the history and a detailed method of tissue array production is described, emphasizing the advantage of the large core size (2.0 mm). Some methological points, including slide storage, microtoming, core size, reliability, and data analysis, are discussed.
Statistics as Topic

To guarantee the inter-reviewer reliability is very important in evaluating the quality of large number of clinical research papers by multiple reviewers. We cannot find reports on statistical methods for evaluating reliability for multiple raters in clinical research field. The purpose of this paper is to introduce the statistical methods focused on kappa statistic and five kinds of loglinear models for, which can be applied when evaluating the reliability of multiple raters. We have applied these methods to the result of a project, in which seven reviewers have evaluated the quality of 33 papers with regard to four aspects of paper contents including study hypothesis, study design, study population, study method, data analysis and interpretation. Among the five loglinear models including Symmetry model, Conditional symmetry model, Quasi-symmetry model, Independence model, and Quasi-independence model, Quasi-symmetry model shows the best model of fitting. And the level of reliability among seven reviewers revealed to be acceptable as meaningful.
Statistics as Topic

No abstract available.
Statistics as Topic*

PURPOSE: We wanted to analyze the citation trend and to find a way to improve the impact factor (IF) of the Journal of the Korean Radiological Society (JKRS). MATERIALS AND METHODS: The number of articles and references, the total citations and self-citations, the IF and the IF excluding self-citations (ZIF) were described by an analysis of Korean Medical Citation Index (KoMCI) during 2000-2005. The total and self citations of the JKRS were compared to that of the Top 5 journals. RESULTS: There was a 57% decrease of papers for 6 years. The Korean references/paper ranged from 0.98-0.85. The number of total citations received steadily decreased from 394 in 2000 to 180 in 2005. The IF (ZIF) of the JKRS has been gradually lowered from 0.142 (0.049) in 2000 to 0.063 (0.059) in 2005. Although the total citations that cited all papers published/the annual number of papers was 55% of that of the top 5 journals, the total citations citing papers published within the recent two years was only 24% of that of the top 5 journals. CONCLUSION: The citation status of the JKRS hassteadily decreased for the recent 6 years, and the IF of the JKRS was very low among all the Korean medical journals. To improve the IF, active advertising for the journal members of the importance of the IF is needed to encourage citing JKRS papers that have been published within the recent two years.
Statistics as Topic

Counting the average number and standard error or standard deviation by popular method of 3 groups also leads to correct results as using Microsoft Excel software. When using Summary Statistics in Descriptive Statistics, we have average value, standard error, standard deviation and other results, in which there was a sample variance. If 2 variances of 2 samples were the similar, t test has been used. Thus, using Microsoft Excel software, we’ll have specific p value. From that, we could infer the greater or smaller results
Statistics Computer

Calculating mean number and standard error or standard deviation by normal calculation method has the correct result as using Microsoft – Excel. Applying Summary Statistics in Descriptive Statistics, we get mean number, standard error, standard deviation and many other results including Sample Variance. If two variances of two samples are the same, we use T- test method. Therefore, we have concrete value of p, which can be use to identify higher or lower expressed value
Statistics ; Computers

PURPOSE: To measure the cement mantle thickness that developed from a rotation of the femoral stem in virtual space made by the broach. MATERIALS AND METHODS: The C stem and Versys stem of the subjects enrolled in this study were examined. A C250/400VZ(Steinbichler Co. Germany) and S/W: Geomagic & CATIA V5 was used to examine the three-dimensional configurations. The axial images were acquired after neutral placement of the femoral stem, horizontal rotation, coronal tilting, and a combination of both. The thickness was measured from the distance between the outer surface of the femoral stem and the closest vertex in the outer contour of the broach in cross-sectional images. RESULTS: The distance was <1 mm at the horizontal rotation of 3 degrees in the C stem, and at 5 degrees in the Versys stem. The distance was <1 mm at varus of 0.25 degrees in the C stem, and touched at 0.8 degrees. In the case of the Versys stem, the femoral stem touched at a varus of 1 degree. A combination of both horizontal and pivot rotation made the distance <1 mm at rotation of all angles. CONCLUSION: It might be necessary to develop a new instrument for the accurate insertion of the femoral stem along the broached space or to modify the stem design to stand against the change in the femoral stem position in the broached space.
Statistics as Topic*

No abstract available.
Statistics as Topic*