Rasch analysis suggests that health assessment questionnaire II is a generic measure of physical functioning for rheumatic diseases: a cross-sectional study

Table 3 ANOVA for Differential Item Functioning by Disease (item in bold suggests possible DIF at the Bonferroni-corrected level of 0.0017)

Item	Class Interval			Disease			Class Interval x Disease			Total
Item	MS	F (df 9)	p	MS	F (df 4)	p	MS	F (df 36)	p	MS	F (df 40)	p
1	1.42	1.61	0.108	0.74	0.84	0.498	1.46	1.65	0.010	55.53	1.573	0.015
2	0.56	0.62	0.778	4.17	4.61	0.001	0.85	0.93	0.573	47.25	1.307	0.101
3	1.31	1.42	0.173	1.61	1.75	0.137	0.69	0.74	0.859	31.26	0.849	0.735
4	1.43	1.38	0.192	3.04	2.94	0.019	0.82	0.78	0.809	41.52	1.005	0.465
5	1.5	1.47	0.152	2.6	2.55	0.038	0.54	0.53	0.989	29.88	0.734	0.889
6	0.68	0.75	0.660	1.13	1.25	0.287	0.94	1.03	0.409	38.24	1.06	0.373
7	2.01	2.7	0.004	0.17	0.22	0.926	0.85	1.13	0.269	31.22	1.046	0.395
8	1.91	2.43	0.010	0.65	0.83	0.506	1.06	1.34	0.087	40.76	1.296	0.108
9	1.66	2.38	0.012	2.4	3.43	0.009	0.33	0.47	0.996	21.57	0.773	0.843
10	0.82	1.04	0.402	1.69	2.14	0.074	0.45	0.56	0.981	22.81	0.726	0.896

ISSN: 1477-7525