# Table 2 t-test to determine the significance of the difference between the mean of R values of antibody-CBMEGV and non-CBM EGVs

Antibody-CBMEGV EGV without CBM EGV inactive without CBM Antibody-CBMEGV vs EGV without CBM Antibody-CBMEGV vs EGV inactive without CBM
Mean R 2.08 1.22 1.41
Number of samples 28 28 22
Total samples     28 + 28 = 56 28 + 22 = 50
2-Tailed probability points of t-distribution at 5 % level     2.01 2.01
Standard error of measurement*     0.26 0.28
Mean difference     2.08 − 1.22 = 0.86 2.08 − 1.41 = 0.67
95 % confidence interval for the difference between population means     0.86 ± 2.01 × 0.26 or 0.43–1.26 0.67 ± 2.01 × 0.28 or 0.19–1.15
As the 95 % confidence interval does not include 0, the difference between the two means is real
1. *Calculated according to the formula SEM = (s2 × (1/n1 + 1/n2))^0.5, where s is the combined variance of the two population involved = (SS1 + SS2)/(n1 + n2 − 2), while SS1 and SS2 are the sum of squares of the respective population and n1 and n2 are the number of samples of the respective population