Table 4.

Classical and Item Response Theory Results for the Medical Data Interpretation Test

	A. Full MDIT							B. Modified MDIT
Item	% Correct	Item-Subscale Correlation	IRT Discrimination	IRT Difficulty	Chi- Square	df	p	Item-Subscale Correlation	IRT Discrimination	IRT Difficulty
1	0.71	0.37	0.80	−1.26	6.11	10	0.80	0.25	0.80	−1.25
2	0.26	0.30	0.53	2.11	9.00	11	0.55	0.18	0.52	2.13
3	0.10	0.15	0.19	11.63	13.40	11	0.26	--	--	--
4	0.37	0.52	1.19	0.57	10.30	11	0.50	0.40	1.19	0.58
5	0.51	0.43	0.66	−0.09	11.40	11	0.45	0.28	0.66	−0.09
6	0.77	0.47	1.72	−1.07	19.20	9	< 0.05	0.40	1.74	−1.06
7–20	0.53	0.47	0.88	−0.19	9.36	10	0.50	0.32	0.87	−0.19
8	0.41	0.21	0.22	1.77	32.80	11	< 0.01	0.07	0.22	1.77
9	0.67	0.34	0.52	−1.46	7.84	11	0.77	0.19	0.52	−1.46
10	0.76	0.48	1.48	−1.06	10.90	10	0.40	0.38	1.49	−1.05
11	0.46	0.41	0.73	0.23	12.30	10	0.26	0.28	0.73	0.23
12	0.81	0.36	1.29	−1.46	7.66	9	0.55	0.32	1.30	−1.45
13–14	0.32	0.15	0.01	57.01	41.3	11	< 0.01	--	--	--
14–15	0.51	0.40	0.62	−0.09	5.94	11	0.85	0.25	0.62	−0.09
16	0.66	0.38	0.69	−1.05	23.30	11	< 0.01	0.25	0.69	−1.05
17	0.41	0.47	1.11	0.40	9.38	10	0.50	0.35	1.11	0.40
18	0.61	0.56	1.66	−0.41	17.90	11	0.08	0.43	1.65	−0.41
19	0.58	0.54	1.51	−0.30	21.60	10	< 0.05	0.43	1.50	−0.30