Obesity has reached epidemic proportions in this century. Although its causes are not well known, its increasing prevalence is not likely to be due to genetic factors or underlying biology. One of the important directions of the medical research is to detect the relationship between the clinical laboratory parameters and obesity. This has led to interest in the role of BMI z-score index, although few studies have focused on the role of the laboratory parameters. This study investigated whether the gender, and the BMI index influenced the association of laboratory parameters. The used statistical method of the analysis is the multidimensional scaling (MDS) which is a set of data analysis techniques that displays the structure of distancelike data — such as correlation — as a geometrical picture.