enlighten has adopted the Welch’s t-test also know as the unequal variances t-test. The purpose of the Welch’s t-test is to compare the current survey results with the previous survey results and determine where there is a variance in the average score is it a positive or negative variation.
We can now go through a worked example of a Food Safety Culture Average Report to explain significance testing further:
Food Safety Culture Average Report
Although we have a variance of minus 0.3 on question 1 the Welch’s t-test has determined this is not a significant variance. This shows that there has been neither a significant improvement or decline in this area.
However on Question 2 we have a variance of plus 1.3 and the Welch’s t-test has determined this as significant. So in this area there has been a significant improvement in this area. When reviewing variance, it is important to determine if the variance is negative or positive.