1. A psychologist decided to design an experiment to test the effects of recreational screen time on children’s academic performance.

The psychologist randomly selected four schools from all the primary schools in her county to take part in the experiment involving Year 5 pupils. Three of the four schools agreed to take part. In total, there were 58 pupils whose parents consented for them to participate. The 58 pupils were then randomly allocated to Group A or Group B.

For the two-week period of the experiment, pupils in Group A had no recreational screen time. Pupils in Group B were allowed unrestricted recreational screen time. At the end of the experiment all pupils completed a 45-minute class test, to achieve a test score.

The results obtained from the experiment are summarised in Table 1.

Table 1 Descriptive statistics for the test performance scores for Group A and Group B

What do the mean and standard deviation values in Table 1 suggest about the effect of recreational screen time on test performance? Justify your answer.