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I was just wondering if I was interpreting my findings correctly. I am evaluating a treatment on a group of children. the class teachers completed the strengths and difficulties questionnaire on the same group of children at time 1(T1) and time 2 (T2) When I initially interpreted the paired sample T-test, I was able to compare the means, and make assumptions as to whether the treatment produced an improvement or not. For the Wilcoxon test, I have the medians. My difficulty is that for example, the hyperactivity scale Scores from 0-5 are in the normal band, scores of 6 are borderline and scores that ranged from 7-10 are abnormal. I’m finding it difficult to determine whether the conclusions I was able to make from the paired T-test will be the same for the Wilcox test. ( I did not check for normality, thus, now having to use the Wilcoxon test) So for example, For the hyperactivity scale for the paired t-test I found: (T1= time1 and T2 =time 2) 1. There was a significant difference in the hyperactivity scores for T1 (M=3.56, SD=2.473) and T2 (M=1.84, SD=2.156); t (74) =7.670, p<0.05. I then stated that: These results suggest that the treatment produced a significant improvement in the hyperactivity scale scores at T2. (I looked at the means for this, even though there was a decline, using the information above about the band scoring it suggested that there was an improvement) is this correct? However, how do I make similar conclusions using medians? For example the prosocial behaviour score band is as follows: 6-10 for normal, 5 =borderline and 0-4 is considered abnormal. below is the beginning of my draft for the write up section. A test of normality reveals (see Appendix a) that the data was not normally distributed, except for the hyperactivity scale at T1 for the Kolmogorov-Smirnov test but not for the Shapiro-Wilk test. For this reason a non- parametric test was used. A Wilcoxon T- test was carried out to compare the T1 scores to the T2 scores on the five SDQ scales and the total difficulties scores. Table1 : Wilcoxon Signed Ranks for the five SDQ scales and the total difficulties scores at T1 and T2. N Mean Rank Sum of Ranks Pro Social Scale at Time 1 - Pro Social Scale at Time 2 Negative Ranks 37a 30.38 1124.00 Positive Ranks 19b 24.84 472.00 Ties 19c Total 75 Hyperactivity Scale at Time 1 - Hyperactivity Scale at Time 2 Negative Ranks 5d 21.50 107.50 Positive Ranks 52e 29.72 1545.50 Ties 18f Total 75 Conduct Problems Scale at Time 1 - Conduct Problems Scale at Time 2 Negative Ranks 12g 19.83 238.00 Positive Ranks 25h 18.60 465.00 Ties 38i Total 75 Emotional Symptoms Scale at Time 1 - Emotional Symptoms Scale at Time 2 Negative Ranks 10j 18.85 188.50 Positive Ranks 34k 23.57 801.50 Ties 31l Total 75 Peer Problems Scale at Time 1 - Peer Problems Scale at Time 2 Negative Ranks 12m 26.58 319.00 Positive Ranks 40n 26.48 1059.00 Ties 23o Total 75 Total SDQ score at Time 1 - Total SDQ score at Time 2 Negative Ranks 8p 34.12 273.00 Positive Ranks 62q 35.68 2212.00 Ties 5r Total 75 *Table 2: Wilcoxon Signed Ranks Test* Pro Social Scale at Time 1 - Pro Social Scale at Time 2 Hyperactivity Scale at Time 1 - Hyperactivity Scale at Time 2 Conduct Problems Scale at Time 1 - Conduct Problems Scale at Time 2 Emotional Symptoms Scale at Time 1 - Emotional Symptoms Scale at Time 2 Peer Problems Scale at Time 1 - Peer Problems Scale at Time 2 Total SDQ score at Time 1 - Total SDQ score at Time 2 Z -2.685a -5.755b -1.735b -3.615b -3.467b -5.687b Asymp. Sig. (2-tailed) .007 .000 .083 .000 .001 .000 a. Based on negative ranks b. Based on positive ranks A Wilcox Signed Rank Test revealed that: *Am I correct in my interpretation here???* There was a significant difference in the pro-social behaviour scale scores for T1 and T2, Z=-2.685, p=0.07. The median score on the pro-social behaviour scale has decreased from T1 (Md=30.38) to T2 (Md=24.84). The results suggest that the treatment produced a significant difference in the pro-social behaviour scale scores. However, *they were better at T1 than at T2.* There was a significant difference in the hyperactivity scale for T1 and T2, Z=-5.755, p<0.05. The median score on the hyperactivity scale has increased from T1 (Md=21.50) to T2 (Md=29.72). These results suggest that NA produced a significant improvement in the hyperactivity scale scores and that at T2. Hope my questions make sense and that you are able to help!