Validation of the World Health Organization Well-Being Index (WHO-5) among medical educators in Hong Kong: a confirmatory factor analysis

Figures & data

Table 1. Fit indices of the WHO-5 for all participants (N = 435)

	χ^2	df	χ^2/df	p	CFI	NFI	IFI	TLI	RMSEA (90% CI)
WHO-5	18.425	4	3.09	0.026	0.99	0.99	0.99	0.98	0.08 (0.05, 0.14)

CFI = comparative fit index; NFI = Bentler-Bonett normed fit index; IFI = incremental fit index; TLI = Tucker-Lewis index; and RMSEA = root mean square error of approximation.

Table 2. Fit indices of the WHO-5 among educators with a medicine background (n = 333)

	χ^2	df	χ^2/df	p	CFI	NFI	IFI	TLI	RMSEA (90% CI)
WHO-5	8.83	3	2.94	0.032	0.99	0.99	0.99	0.98	0.07 (0.05, 0.14)

Note: CFI = comparative fit index; NFI = Bentler-Bonett normed fit index; IFI = incremental fit index; TLI = Tucker-Lewis index; and RMSEA = root mean square error of approximation.

Table 3. Differences in WHO-5 scores across age groups

Age Groups	Mean (SD)	F	p	Scheffé Post-hoc comparison
Group 1: 20–39 (n = 94)	56.51 (20.20)	8.04	<0.001	1 < 4 2 < 4
Group 2: 40–49 (n = 144)	55.86 (21.10)
Group 3: 50–59 (n = 106)	62.79 (18.52)
Group 4: 60 and above (n = 70)	68.84 (21.22)

SD = standard deviation.

Table 4. Gender differences of the WHO-5

Instrument	Male (n = 280)	Female (n = 136)
	Mean (SD)	Mean (SD)	t (414)	p
WHO-5	60.67 (21.19)	58.41 (19.85)	1.04	0.30

SD = standard deviation; p = empirical-level of two-tailed testing; t (414) = t-value with 414 degrees of freedom.

Figure 1. Confirmatory factor analysis of one-factor WHO-5 model.

Table 5. Differences in the WHO-5 by professional background

Instrument	Medicine (n = 333)	Other Healthcare Professionals (n = 84)
	Mean (SD)	Mean (SD)	t (415)	p
WHO-5	61.23 (19.61)	54.10 (23.92)	2.84	<0.01

Other Healthcare Professionals include Biomedical Sciences, Nursing and Pharmacy; p = empirical-level of two-tailed testing; t (415) = t-value with 415 degrees of freedom.

Table 1. Characteristics of participants

Participant characteristics (N = 435)
Age, no. (%)^a
20–29	8 (1.9)
30–39	86 (20.5)
40–49	144 (34.3)
50–59	106 (25.2)
≥ 60	70 (16.7)
Prefer not to say	6 (1.4)
Gender, no. (%)^a
Male	280 (66.7)
Female	136 (32.4)
Prefer not to say	4 (1.0)
Ethnicity, no. (%)^a
Chinese	394 (93.8)
Caucasian	9 (2.1)
Mixed/Multiple	4 (1.0)
Others	7 (1.7)
Prefer not to say	6 (1.4)
Professional Background, no. (%)^a
Biomedical Sciences	31 (7.4)
Medicine	333 (79.9)
Nursing	30 (7.2)
Pharmacy	6 (1.4)
Other	17 (4.1)
Highest Professional Qualification, no. (%)^a
Bachelor’s degree	29 (6.9)
Specialist qualification	186 (44.3)
Master’s degree	67 (16.0)
Doctorate	132 (31.4)
Other	6 (1.4)
Years Worked as health professions educator, no. (%)^a
0–4	50 (11.9)
5–9	72 (17.1)
10–14	74 (17.6)
15–19	47 (11.2)
≥ 20	177 (42.1)
Employment status, no. (%)^a
Full-time	255 (60.7)
Part-time	14 (3.3)
Honorary	148 (35.2)
Temporary	1 (0.2)
Other	2 (0.5)

^aNumbers do not add up to 435 due to missing data; percentage is calculated based on the number of complete data.

Table 2. Basic statistics of the scales

Scales	Range	Mean (SD)	Cronbach’s alpha
WHO-5	0–100	59.6 (20.9)	0.93
CD-RISC2	2–8	5.8 (1.3)	0.67
WHO-5 = 5-item World Health Organization Well-being Index; CD-RISC2 = 2-item Connor-Davidson Resilience Scale; SD = standard deviation.

Table 3. Internal consistency of WHO-5: Cronbach’s alpha of WHO-5, Corrected item-total correlation, and Cronbach’s alpha if the item is deleted from the scale

Item	Cronbach’s alpha	Corrected item-total correlation	Cronbach’s alpha if item deleted
WHO-5 (all 5 items)	0.93	-	-
1. I have felt cheerful and in good spirits.		0.86	0.91
2. I have felt calm and relaxed.		0.82	0.92
3. I have felt active and vigorous.		0.85	0.91
4. I woke up feeling fresh and rested.		0.79	0.93
5. My daily life has been filled with things that interest me.		0.80	0.92

Table 4. Inter-item correlation of the five items of the WHO-5

Item	1	2	3	4	5
1. I have felt cheerful and in good spirits.	-	0.78	0.79	0.70	0.75
2. I have felt calm and relaxed.		-	0.75	0.73	0.67
3. I have felt active and vigorous.			-	0.71	0.76
4. I woke up feeling fresh and rested.				-	0.71
5. My daily life has been filled with things that interest me.					-

Note: All values are significant (p < 0.001).