Dissertation - World Federation of Music Therapy

Results – inferential statistics and effect sizes
Table 5. 4 Wilcoxon matched pairs test: Comparison of pre-test scores with posttest
scores and follow-up scores in SOC
Measure Z P value
SOC QoL overall pre-test difference to post-test -2,198 .028*
SOC QoL overall pre-test difference to follow-up -2,207 .027*
SOC Manageability pre-test difference to post-test -2,226 .026*
SOC Manageability pre-test difference to follow-up -,135 .892
SOC Meaningfulness pre-test difference to post-test -,946 .344
SOC Meaningfulness pre-test difference to follow-up -,738 .461
SOC Comprehensibility pre-test difference to post-test -2,032 .042*
SOC Comprehensibility pre-test difference to follow-up -2,214 .027*
Table 5.4 gives the results of a two-tailed Wilcoxon matched pairs test that was
computed to compare pre-test scores with post-test and follow-up scores. The results
show that quality of life was found to be significantly higher at post-test than at pre-
test (p = .028), and also significantly higher at follow-up than at pre-test (p = 0.27).
Manageability sub-scores were significantly higher at post-test than at pre-test (p =
.026). Comprehensibility sub-scores were significantly higher both at post-test (p
=.042) and at follow-up (p = 0.27) than at pre-test.
Descriptive statistical analysis was undertaken to calculate the degree of the treatment
effect at post-test and at follow up.
Table 5. 5 Effect sizes measured at post-test and follow-up for total SOC scores
Cohens d
ES SOC pre-test to post test 0.623
ES SOC pre-test to follow up 0.405
The effect of the intervention on quality of life found at post-test was medium
(Cohen’s d = 0.623), and at follow up was small to medium (Cohen’s d = 0.405).
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