Table 4.

Parameter estimates from item response theory analysis of the revised PEQ-GP GP scale (n = 567), sorted by core GP aspects^a.

	a	b1	b2	b3	b4	S-X2	P value
GP patient centredness
1. GP takes you seriously	3.87	−2.69	−2.29	−1.40	−0.10	28.82	0.422
2. GP spends enough time with you	2.36	−2.84	−1.88	−0.93	0.54	47.82	0.359
3. GP talks to you in a way you understand	2.65	−3.19	−2.50	−1.78	−0.00	28.56	0.381
4. GP is professionally competent	3.32	−3.33	−2.48	−1.39	0.10	39.60	0.167
5. GP shows interest in your situation	4.28	−2.71	−1.93	−1.09	0.10	46.63	0.027
6. GP includes you as much as you would like in decisions concerning you	3.25	−2.76	−2.11	−1.10	0.26	41.10	0.16
GP information
7. GP provide sufficient information about health problems and treatment	4.07	−2.49	−1.83	−0.87	0.37	37.74	0.103
8. GP provide sufficient information about use/side effects of medication	2.08	−2.37	−1.25	−0.34	1.03	59.62	0.346
GP coordination
9. GP is good at coordinating the range of health services available to you	2.86	−3.27	−2.00	−0.96	0.53	37.63	0.307
10. GP cooperates well with other services you need	2.54	−2.75	−2.00	−0.92	0.57	34.56	0.629
GP enablement
11. Contact with GP make you better able to understand your health problems	3.21	−2.41	−1.59	−0.59	0.82	28.31	0.816
12. Contact with GP make you better able to cope with your health problems	2.92	−2.33	−1.50	−0.40	0.97	43.10	0.347
13. Contact with GP better help you to stay healthy	2.31	−2.54	−1.50	−0.27	1.13	59.65	0.142
GP overall assessment
14. Overall satisfaction with GP	5.71	−2.50	−2.02	−1.16	−0.10	20.21	0.629
15. Recommend GP to family/friends	3.69	−1.94	−1.51	−0.73	0.17	45.05	0.306

^aGraded response model. a: discrimination; b1–b4: thresholds. S–X² represents item fit statistics, with P values <0.05 indicating lack of fit.