Item bias on the geriatric depression scale (GDS): investigating the quality and generalizability of GDS on Chinese and Korean community-dwelling elderly population

Table 6 The effect size for significantly detected DIF

Dimension	Item	Hybrid IRT-Logistic Regression
Dimension	Item	\( {R}_{12}^2 \)	\( {R}_{13}^2 \)	\( {R}_{23}^2 \)	Δβ1
Dimension 1: Agitation	GDS6	0.100	0.119	0.019	0.178
	GDS13	0.053	0.057	0.003	0.145
	GDS29	0.107	0.109	0.002	0.094
Dimension 2: Cognitive concerns	GDS14	0.161	0.183	0.022	0.507
	GDS26	0.009	0.048	0.039	0.023
	GDS20	0.079	0.098	0.019	0.129
Dimension 3: Dysphoria	GDS2	0.032	0.032	0.000	0.074
	GDS10	0.017	0.027	0.010	0.015
	GDS23	0.045	0.051	0.006	0.134
	GDS25	0.007	0.063	0.056	0.040
Dimension 4: Vigor/withdrawal	GDS5	0.069	0.070	0.001	0.148
	GDS12	0.067	0.068	0.000	0.063
	GDS15	0.000	0.036	0.035	0.000
	GDS17	0.007	0.043	0.036	0.019
	GDS19	0.001	0.017	0.016	0.003
	GDS20	0.081	0.089	0.008	0.113
	GDS21	0.026	0.029	0.003	0.223
	GDS28	0.037	0.062	0.025	0.042

ISSN: 1471-2318