Last update:
03-Aug-2013

As research articles include statistical methods and terms, knowledge of at least the fundamental principles of statistics is essential for writing and evaluating research articles. Particular attention must be paid to the statistical methods and terms used in articles, in order to avoid misinterpretation and confusion. In the methods section certain things should be declared with clarity, including (a) the predetermined level of statistical significance (alpha value), (b) the management of quantitative variables and (c) the methodology for checking the normality of quantitative variables. In the results section, confidence intervals should be presented. The exact values of statistical significance (p values) should be reported, and not just whether they are greater or less than 0.05. With regard to quantitative variables that follow a normal distribution, the mean value is used, with standard deviation to describe the variability, while for those that do not follow a normal distribution the median value, with range or interquartile range is used. Both absolute and relative frequencies need to be used in order to reach a safe conclusion. It should be remembered that in Greek, decimal numbers are reported with a comma, while in English with a period (full stop). The reverse applies to numbers in thousands, which in English are indicated with a comma, while in Greek they are indicated reported with a period (full stop).

Key words: Confidence interval, Methods, p value, Research article, Results, Statistics.