The article discusses the importance of descriptive statistics and normality tests in biomedical research. Descriptive statistics provide simple summaries of sample data, including measures of central tendency (mean, median, mode) and dispersion (variance, standard deviation, standard error, quartiles, interquartile range, percentile, range, and coefficient of variation). Normality testing is crucial for selecting appropriate statistical methods, such as parametric or nonparametric tests, and for comparing groups. Various methods for testing normality, including numerical and visual methods, are discussed, with each method having its own advantages and disadvantages. The article emphasizes the significance of normality testing, especially for small sample sizes, and provides examples using mean arterial pressure (MAP) data from 15 patients. The study concludes that while various normality tests can be used, the Shapiro-Wilk test is recommended for small samples, and other methods can be employed for larger samples. The article also highlights the importance of considering the sample size when interpreting normality tests.The article discusses the importance of descriptive statistics and normality tests in biomedical research. Descriptive statistics provide simple summaries of sample data, including measures of central tendency (mean, median, mode) and dispersion (variance, standard deviation, standard error, quartiles, interquartile range, percentile, range, and coefficient of variation). Normality testing is crucial for selecting appropriate statistical methods, such as parametric or nonparametric tests, and for comparing groups. Various methods for testing normality, including numerical and visual methods, are discussed, with each method having its own advantages and disadvantages. The article emphasizes the significance of normality testing, especially for small sample sizes, and provides examples using mean arterial pressure (MAP) data from 15 patients. The study concludes that while various normality tests can be used, the Shapiro-Wilk test is recommended for small samples, and other methods can be employed for larger samples. The article also highlights the importance of considering the sample size when interpreting normality tests.