A Scale for Measuring Electronic Patient Engagement Behaviors: Development and Validation

Figures & data

Figure 1 The process of developing the measured items for the EPEB scale.

Figure 2 The EPEB scale components.

Table 1 Reliability Test, Exploratory Factor Analysis and Rasch Analysis of the Pilot Survey

Items	Reliability test			EFA				Rasch analysis
	CITC	Cronbach’s α	α if items deleted	Dimensions				PTMEA-CORR	MNSQ infit	MNSQ outfit
				1	2	3	4
Dimension I: disease information search		0.838
Item 1	0.621		0.811	0.742	--	--	--	0.50	1.28	1.37
Item 2	0.720		0.783	0.851	--	--	--	0.53	1.21	1.21
Item 3	0.657		0.801	0.736	--	--	--	0.56	1.14	1.12
Item 4	0.665		0.799	0.742	--	--	--	0.54	1.12	1.16
Item 5	0.549		0.831	0.560	0.446	--	--	0.57	1.07	1.09
Dimension II: doctor-patients interaction		0.906
Item 6	0.544		0.907	0.527	0.465	--	--	0.58	1.03	0.97
Item 7	0.699		0.895	0.462	0.684	--	--	0.64	0.92	0.87
Item 8	0.821		0.884	--	0.784	--	--	0.72	0.72	0.70
Item 9	0.712		0.894	--	0.667	--	--	0.70	0.83	0.88
Item 10	0.626		0.901	--	0.605	--	--	0.66	0.95	0.89
Item 11	0.811		0.884	--	0.815	--	--	0.72	0.75	0.73
Item 12	0.786		0.887	--	0.789	--	--	0.71	0.78	0.78
Item 13	0.610		0.903	--	0.642	--	--	0.63	1.02	1.08
Dimension III: social interaction among patients		0.868
Item 14	0.708		0.839	--	--	0.859	--	0.57	1.27	1.33
Item 15	0.832		0.785	--	--	0.826	--	0.65	0.99	1.01
Item 16	0.786		0.805	--	--	0.811	--	0.61	1.09	1.10
Item 17	0.569		0.887	--	--	0.443	0.616	0.62	1.13	1.12
Dimension IV: disease self-monitoring		0.908
Item 18	0.780		0.899	--	--	--	0.811	0.64	1.01	1.00
Item 19	0.854		0.837	--	--	--	0.842	0.68	0.87	0.92
Item 20	0.816		0.868	--	--	--	0.847	0.68	0.89	0.90

Notes: --Represents that the factor load is lower than 0.4, and the common degree of each item is between 0.507 and 0.863.

Table 2 Exploratory Factor Analysis After Removing Unqualified Items

No	Items	Dimensions
		1	2	3	4
	Dimension I: disease information search (DIS)
1	Search information on the diagnosis and treatment online (DIS 1)	0.763	--	--	--
2	Browse for self-care information online (DIS 2)	0.881	--	--	--
3	Search information on well-known hospitals and doctors online (DIS 3)	0.745	--	--	--
4	Browse the electronic reports of medical examination (DIS 4)	0.719	--	--	--
	Dimension II: doctor-patients interaction (DPI)
5	Share information about my condition with medical staff online (DPI 1)	--	0.770	--	--
6	Share my needs and preferences with medical staff online (DPI 2)	--	0.843	--	--
7	Seek expert opinions from different doctors through online consultation (DPI 3)	--	0.718	--	--
8	Offer online feedback on treatment effectiveness to medical staff (DPI 4)	--	0.746	--	--
9	Submitting complaints about my experience to the healthcare provider online (DPI 5)	--	0.604	--	--
	Dimension III: social interaction among patients (SIP)
10	Join patient online discussion groups (SIP1)	--	--	0.871	--
11	Share information and experiences to patients suffering from my same disease via social media (SIP2)	--	--	0.843	--
12	Seek or provide emotional support via social media (SIP3)	--	--	0.827	--
	Dimension IV: disease self-monitoring (DSM)
13	Use wearable devices or health apps to monitor health data (DSM1)	--	--	--	0.836
14	Use health apps for symptom self-assessment, diet management, and data tracking (DSM2)	--	--	--	0.854
15	Use health apps to record illness status and physical feelings (DSM3)	--	--	--	0.838

Table 3 CR and Item-Total Correlation for Each Item of EPEB Scale

No	Items	Critical Ratio Method		Correlation Coefficient Method
		CR	P values	Item-total correlation	P values
1	DIS1	18.965	<0.001	0.623	<0.001
2	DIS2	21.906	<0.001	0.675	<0.001
3	DIS3	18.870	<0.001	0.644	<0.001
4	DIS4	20.143	<0.001	0.680	<0.001
5	DPI1	25.099	<0.001	0.746	<0.001
6	DPI2	29.657	<0.001	0.802	<0.001
7	DPI3	29.377	<0.001	0.761	<0.001
8	DPI4	30.361	<0.001	0.794	<0.001
9	DPI5	23.048	<0.001	0.721	<0.001
10	SIP1	21.588	<0.001	0.683	<0.001
11	SIP2	26.711	<0.001	0.763	<0.001
12	SIP3	25.740	<0.001	0.750	<0.001
13	DSM1	22.747	<0.001	0.692	<0.001
14	DSM2	22.260	<0.001	0.676	<0.001
15	DSM3	25.121	<0.001	0.736	<0.001

Table 4 The Reliability and Convergence Validity of the EPEB Scale

No	Items	Standardized Regression Weights	Composite Reliability	AVE	Cronbach’s α
1	DS1	0.724	0.856	0.598	0.865
2	DS2	0.808
3	DS3	0.814
4	DS4	0.743
5	DPI1	0.763	0.897	0.637	0.904
6	DPI2	0.847
7	DPI3	0.815
8	DPI4	0.832
9	DPI5	0.728
10	SIP1	0.812	0.908	0.767	0.904
11	SIP2	0.937
12	SIP3	0.874
13	DSM1	0.823	0.901	0.752	0.900
14	DSM2	0.873
15	DSM3	0.904

Table 5 Fit Indices of Factor Structure of EPEB Scale

Indicator	c^2/dƒ	CFI	NFI	GFI	SRMR	RMSEA
Standard	2~5	>0.9	>0.9	>0.9	<0.08	<0.10
Single-factor	27.294***	0.758	0.752	0.696	0.095	0.176
Two-factor	21.700***	0.812	0.805	0.733	0.089	0.156
Three-factor	18.095***	0.841	0.834	0.778	0.068	0.142
Four-factor (first-order)	3.784**	0.976	0.968	0.955	0.038	0.057
Four-factor (second-order)	3.771***	0.975	0.967	0.953	0.039	0.057

Notes: ***Represent a p-value lower than 0.001; **Represent a p-value lower than 0.01.

Abbreviations: X²/df, normed Chi-squared; df, degrees of freedom; CFI, comparative fit index; RMSEA, root mean square of approximation; SRMR, standardized root mean square residual.

Figure 3 Path coefficient of four-factor EPEB scale.

Table 6 Cross-Sex Measurement Equivalence Test of EPEB Scale

Model	X^2/df	CFI	TLI	SRMR	RMSEA	Model comparison	ΔCFI	ΔTLI	ΔRMSEA
Male	2.424***	0.965	0.955	0.043	0.071	--	--	--	--
Female	2.754***	0.977	0.969	0.041	0.056	--	--	--	--
M	2.590***	0.973	0.964	0.043	0.043	--	--	--	--
M1	2.521***	0.972	0.966	0.042	0.042	M1 vs M	−0.001	0.002	−0.001
M2	2.448***	0.970	0.967	0.053	0.041	M2 vs M1	−0.002	0.001	−0.001
M3	2.462***	0.966	0.967	0.053	0.041	M3 vs M2	−0.004	0.000	0.000

Notes: ***Represent a p-value lower than 0.001.