**3.5 Prognostic significance of the number of copies of EBV DNA**

In order to clarify the prognostic significance of the number of EBV DNA in saliva samples, a linear regression analysis was carried out with the calculation of the coefficients of determination R2 (R Square) and using the Durban-Watson test and analysis of variance (ANOVA "Analysis of Variance") using criterion F and the calculation of the standardized coefficient beta (ß) with a 95% confidence interval. The results of the F criterion and the ß coefficient, indicating the significance of the obtained regression models, are presented below.

