Table 2.

Summary statistics for non-parametric comparison of composite z-scores for four cohorts of DEP and GEP students

Cohort (Year)	DEP Median	GEP Median	DEP IQR	GEP IQR	U	p	Effect (r)
Cohort 1 SC1 (2008-2009)	-1.07	2.44	4.64	3.71	2390	<0.01	0.35
Cohort 1 SC2 (2009-2010)	-0.33	0.58	1.42	0.76	2464	<0.01	0.33
Cohort 2 SC1 (2009-2010)	-0.82	2.42	4.87	3.25	2449	<0.01	0.40
Cohort 2 SC2 (2010-2011)	-0.05	0.50	1.38	1.31	3248	<0.01	0.28
Cohort 3 SC1 (2010-2011)	-1.29	2.88	5.04	3.05	2000	<0.01	0.45
Cohort 3 SC2 (2011-2012)	-0.21	0.61	1.44	0.75	2426	<0.01	0.37
Cohort 4 SC1 (2011-2012)	-0.99	2.78	5.29	3.80	2728	<0.01	0.40
Cohort 4 SC2 (2012-2013)	-0.21	0.58	1.39	1.04	2924	<0.01	0.35

Data shown include median scores, interquartile ranges (IQR), the test statistic U, the p-value and effect size (r).