ABSTRACT
Individual measurements prior to intervention act like a “control group” or a reflection of the population. The measurement of each individual difference between the prior and post-intervention reflects the effect or difference of the intervention. The Wilcoxon Signed Rank test measures before and after change like the McNemar; however, the magnitude of the change can be determined since the measurement is ordinal. There was a significant positive change from the pre- to post-measurement of the perception of social work. Different names are used such as repeated, paired or replicated indicating that the same people are assessed two times and the mean of the first measurement is compared to the mean of the second measurement. Self-esteem was measured on a scale with a total score that ranged from 4 and 16, with higher scores indicating better self-esteem. The chapter demonstrates that the use of the paired t-test by analyzing the results of an intervention for teenage girls with low self-esteem.
