Table 2 Bivariate correlations of knowledge gain and pre-test knowledge with potential influencing variables

1

2

3

4

5

6

1. Knowledge gain

–

–

–

–

–

–

2. Knowledge pre-test

− 0.77**

–

–

–

–

–

3. Age

−0.16

0.46^**

–

–

–

–

4. Family language

− 0.19

0.11

0.18

–

–

–

5. Cognitive capacities

0.10

0.06

−0.05

−0.19

–

–

6. Ability to concentrate

0.15

0.00

−0.01

−0.09

0.71^**

–

1

2

3

4

5

6

7

1. Knowledge gain

–

–

–

–

–

–

–

2. Knowledge pre-test

−0.48^**

–

–

–

–

–

–

3. Age

−0.53^**

0.53^**

–

–

–

–

–

4. Family language

0.04

−0.30

−0.12

–

–

–

–

5. Galactosemia

0.18

0.12

− 0.32

0.19

–

–

–

6. School type

−0.13

− 0.14

0.20

− 0.03

−0.27

–

–

7. Testing site

− 0.07

0.10

0.02

0.09

0.32

0.04

–