. 2023 May 17;11:1147862. doi: 10.3389/fpubh.2023.1147862

Table 2.

Evaluation of items based on IRT and results of DIF analysis of the original version of the Chinese Resident Health Literacy Scale in Sample A.

Item abbreviation		Correct (%)	Correlation to dimension score	IRT parameters			DIF						Kept
				IRT parameters			Cognitive Status			Education Level
				Difficulty	Discrimination	Information level	Statistic	p	R²	Statistic	p	R²
Dimension1: Knowledge and attitudes
A01	Prevention of the flu	79.35	0.43	−1.44	1.13	0.32	0.52	0.74	0.0001	0.65	0.52	0.0002	Yes
A02	Health care products	79.20	0.26	0.58	1.42	0.08	<0.001	0.99	<0.0001	5.20	0.07	0.0017	No
A03	Infusion	79.86	0.42	−1.43	1.08	0.29	0.22	0.76	0.0001	0.64	0.52	0.0002	Yes
A05	Health products	79.11	0.31	−2.26	0.63	0.10	<0.001	0.99	<0.0001	5.20	0.07	0.0017	No
A10	Body temperature	78.03	0.23	−3.57	0.37	0.03	7.90	0.04	0.0026	7.16	0.78	0.0002	No
B01	The definition of health	71.90	0.52	−0.92	1.43	0.51	0.20	0.76	<0.0001	4.63	0.08	0.0011	Yes
B03	Hepatitis B	56.30	0.38	−0.96	0.75	0.14	0.99	0.63	0.0003	3.87	0.05	0.0024	No
B04	Blood pressure measurement	48.75	0.38	−0.40	0.69	0.12	0.79	0.63	0.0002	0.03	0.78	0.0003	No
B06	Early symptoms of cancer	51.32	0.41	0.11	0.82	0.17	2.27	0.32	0.0006	5.71	0.90	<0.0001	No
B07	Management of gas poisoning	77.12	0.40	−1.55	0.93	0.21	4.91	0.08	0.0014	2.51	0.19	0.0007	Yes
B08	Tuberculosis treatment	61.68	0.57	−0.05	1.55	0.59	8.59	0.04	0.0019	4.38	0.10	0.0011	No
B09	Toxic and hazardous work	70.60	0.47	−0.96	1.16	0.34	6.48	0.05	0.0017	4.72	0.08	0.0013	Yes
B10	Harm of iodine deficiency	64.01	0.36	−0.79	0.63	0.10	0.09	0.80	<0.0001	0.27	0.87	<0.0001	No
B13	Vaccines for children	63.29	0.45	−0.69	0.93	0.19	0.37	0.76	0.0001	0.44	0.07	0.0016	No
B17	Meaning of warning diagram	69.47	0.51	−0.79	1.35	0.45	3.98	0.13	0.0010	5.25	0.07	0.0013	Yes
C02	Medical visits	70.31	0.45	−0.98	1.08	0.29	0.27	0.76	0.0001	6.20	0.07	0.0017	Yes
C03	Liver	14.30	0.45	−1.49	1.35	0.46	14.06	0.00	0.0039	7.69	0.08	0.0010	No
C06	Packaged food	37.29	0.28	2.75	0.73	0.13	0.89	0.63	0.0003	0.93	0.66	0.0001	No
C07	Treatment of sick and dead livestock	68.27	0.50	−0.70	1.22	0.37	1.04	0.64	0.0003	0.04	0.87	<0.0001	Yes
C15	Pesticide storage	58.44	0.49	−0.38	1.13	0.32	5.13	0.08	0.0013	8.44	0.06	0.0021	Yes
D03	Control weight	61.64	0.48	−0.55	1.07	0.28	0.14	0.78	<0.0001	0.77	0.52	0.0002	Yes
D04	Obesity-related disease	67.79	0.46	−0.86	1.07	0.27	6.27	0.05	0.0017	2.22	0.21	0.0006	Yes
Dimension2: Behavior and lifestyles
A04	Fruits and vegetables	80.75	0.37	−2.17	0.70	0.12	0.35	0.74	0.0001	0.75	0.78	0.0001	No
A06	Depression	86.24	0.36	−2.33	0.88	0.19	4.80	0.23	0.0015	1.07	0.05	0.0022	No
A09	Chronic disease treatment	62.95	0.33	−1.37	0.41	0.04	1.42	0.64	0.0005	0.04	0.78	0.0001	No
B05	Dangers of smoking	52.66	0.50	−0.05	0.99	0.24	2.38	0.49	0.0006	1.46	0.73	0.0004	Yes
B11	Hydration	62.57	0.46	−0.63	0.84	0.17	0.08	0.89	<0.0001	0.49	0.78	0.0002	No
B12	National basic public health service	40.07	0.49	0.51	1.05	0.27	0.28	0.74	0.0001	2.93	0.67	0.0008	Yes
B14	Fever	77.43	0.4	−1.80	0.80	0.15	1.11	0.64	0.0003	0.23	0.90	<0.0001	No
B15	Adverse reactions	79.52	0.33	−2.30	0.62	0.09	0.03	0.89	<0.0001	0.49	0.26	0.0008	No
B19	Medical visits	71.18	0.62	−0.91	1.29	0.41	0.84	0.64	0.0002	0.15	0.80	<0.0001	Yes
B21	Opening windows for ventilation during flu season	70.05	0.45	−0.98	0.99	0.24	0.88	0.64	0.0002	0.53	0.78	0.0001	Yes
C01	Promoting mental health	52.25	0.58	0.03	1.92	0.90	1.34	0.64	<0.0001	1.86	0.69	<0.0001	Yes
C04	Fever and rash in children	56.09	0.6	−0.17	2.00	0.97	0.47	0.74	<0.0001	2.34	0.67	<0.0001	Yes
C09	Benefits of eating soy products	31.60	0.43	0.95	1.05	0.27	2.63	0.49	0.0007	0.24	0.78	0.0001	Yes
C10	Health benefits of exercise	45.11	0.54	0.23	1.62	0.63	0.02	0.89	<0.0001	0.01	0.96	<0.0001	Yes
C12	Coughing and sneezing	46.90	0.38	0.29	0.53	0.07	5.75	0.23	0.0018	5.89	0.26	0.0005	No
C13	Medical visits	67.75	0.52	−0.72	1.21	0.36	0.41	0.74	0.0001	0.25	0.78	0.0001	Yes
Dimension3: Health-related skills
B16	Treatment of virulent infectious diseases	83.81	0.44	−1.63	1.24	0.36	0.03	0.93	<0.0001	0.14	0.26	0.0007	Yes
B18	Toll-free health hotline number	34.90	0.41	1.00	−0.75	0.24	2.63	0.27	0.0007	0.07	0.01	0.0033	No
B20	OTC	28.37	0.42	1.38	0.79	0.15	2.54	0.27	0.0007	0.24	0.42	0.0002	No
B22	Glass thermometer	62.74	0.44	−0.79	0.7	0.12	0.20	0.85	0.0001	0.28	0.49	0.0003	No
B25	Mild burns	73.21	0.45	−1.31	0.92	0.19	2.10	0.29	0.0006	0.05	0.10	0.0010	No
B26	Fire handling	46.14	0.4	0.41	0.55	0.07	0.01	0.93	<0.0001	0.37	0.24	0.0018	No
C08	Cardiac arrest	59.07	0.52	−0.31	1.09	0.28	4.24	0.16	0.0011	0.10	0.36	0.0004	Yes
C11	Hypoglycemic products	70.94	0.47	−1.03	0.99	0.23	7.51	0.07	0.0020	0.41	0.26	0.0006	Yes
C14	Benefits of breastfeeding for babies	44.94	0.52	0.24	1.13	0.30	0.34	0.84	0.0001	2.64	0.26	0.0006	Yes
C16	Lightning weather outdoors	82.40	0.42	−1.80	0.99	0.23	0.61	0.75	0.0002	0.04	0.42	0.0002	Yes
D01	Calculation of BMI	35.13	0.54	0.61	1.62	0.63	6.43	0.07	0.0013	0.05	0.14	0.0011	Yes
D02	Classification of BMI	42.50	0.56	0.28	1.69	0.69	0.14	0.85	<0.0001	1.22	0.26	<0.0001	Yes

R²: DIF magnitude, applying the cut-offs of: <0.13 = negligible; 0.13–0.26 = moderate; >0.26 = not negligible (53).