Table 3. Wilcoxon test to explore effect of module on student’s pain management knowledge.

Variables	n	Mean (SD)	Median (IQR)	Z-stat	Effect Size (95%CI)	NR PR Ties
Pre-test Overall	219	41.0(13.3)	40.00(20.00)	-11.3**	1.3(-0.2 to 2.7)	19 185 15
Post-test Overall	219	63.2(16.7)	60.00(25.00)
Pre-test BUK	89	40.7(15.7)	35.00(15.00)	-7.4**	1.4(-2.5 to 5.4)	9 75 5
Post-test BUK	89	68.7(20.5)	65.00(37.50)
Pre-test ESUTH	8	38.1(10.0)	35.00(17.50)	-2.4*	2.2(0.2 to 4.2)	0 7 1
Post-test ESUTH	8	60.0(12.0)	60.00(21.25)
Pre-test NAU	9	45.0(13.0)	50.00(15.00)	-2.4*	1.5 (-1.1 to 4.0)	1 7 1
Post-test NAU	9	64.4(15.5)	60.00(32.50)
Pre-test UNILAG	93	41.9(11.8)	40.00(20.00)	-7.0**	1.4 (-0.9 to 3.6)	9 77 7
Post-test UNILAG	93	58.9(12.5)	60.00(15.00)
Pre-test UNN	20	36.8(9.1)	37.50(13.75)	-3.8**	2.5(0.9 to 4.1)	0 19 1
Post-test UNN	20	59.0(8.1)	60.00(15.00)

Z = Wilcoxon-Ranked test; BUK = Bayero University, Kano; ESUT = Enugu State University of Science and Technology, Enugu; NAU = Nnamdi Azikiwe University, Awka; UNILAG = University of Lagos; UNN = University of Nigeria Nsukka; PR = Positive Ranks, NR = Negative Ranks;

* p<0.05;

** p<0.001.