Table 2. Estimated parameters for the 15 items of the Japanese Health Knowledge Test.

Item number	Alpha (slope parameter)				Gamma (location parameter)
	Category				Category
	1	2	3	4	1	2	3	4
1	0.00	0.07	0.46	0.36	0.00	0.88	2.04	−0.41
2	0.00	0.62	1.56	0.91	0.00	0.77	2.99	2.06
3	0.00	−1.53	−0.30	−0.45	0.00	−2.25	0.13	0.64
4	0.00	−0.69	0.33	−0.47	0.00	1.26	2.04	0.21
5	0.00	2.70	2.19	1.49	0.00	4.65	2.58	1.93
6	0.00	1.67	0.94	2.26	0.00	3.28	0.42	0.64
7	0.00	0.63	−1.79	−2.02	0.00	0.71	−2.68	−3.15
8	0.00	0.26	0.23	1.02	0.00	−0.16	1.08	2.25
9	0.00	−1.07	−0.87	−1.04	0.00	−2.04	−2.50	−2.13
10	NA	0.00	1.53	NA	NA	0.00	3.54	NA
11	0.00	0.56	NA	0.32	0.00	2.53	NA	0.69
12	0.00	−0.74	−0.87	0.24	0.00	−1.42	−0.71	−0.17
13	0.00	−1.52	0.96	NA	0.00	−2.56	0.88	NA
14	0.00	0.81	−0.33	−0.25	0.00	1.37	−0.50	−0.06
15	0.00	−1.18	−0.21	0.69	0.00	−0.91	−0.34	1.12

Values for category 1 were set to 0 for estimating parameters.

NA, not available.