Psychometrics of chronic liver disease questionnaire in Chinese chronic hepatitis B patients

Table 1 Social-demographic characteristics n (%)

Items	Total (n = 460)	CHB (n = 323)	CHB-related cirrhosis (n = 137)
Age (yr)
18-35	240 (52.2)	216 (90.0)	24 (10.0)
36-50	152 (33.0)	87 (57.2)	65 (42.8)
51-65	64 (13.9)	20 (31.3)	44 (68.8)
66-76	4 (0.9)	0 (0.0)	4 (100.0)
mean ± SD	35.75 ± 12.82	31.53 ± 10.94	45.71 ± 11.36
Gender
Male	305 (66.3)	212 (69.5)	93 (30.5)
Female	155 (33.7)	111 (71.6)	44 (28.4)
Marital status
Single	125 (27.2)	119 (95.2)	6 (4.8)
Married	328 (71.3)	200 (61.0)	128 (39.0)
Others	7 (1.5)	4 (57.1)	3 (42.9)
Education level
No schooling and primary	63 (13.7)	31 (49.2)	32 (50.8)
Secondary	311 (67.6)	217 (69.8)	94 (30.2)
Tertiary	86 (18.7)	75 (87.2)	11 (12.8)
Occupation
Peasants	153 (33.3)	73 (47.7)	80 (52.3)
Non-peasants	307 (66.7)	250 (81.4)	57 (18.6)
Annual per capita household incomes (RMB)
< 5000	236 (51.3)	147 (62.3)	89 (37.7)
5000-9999	111 (24.1)	88 (79.3)	23 (20.7)
≥ 10000	113 (24.6)	88 (77.9)	25 (22.1)
Received ALT test
Yes	375 (81.5)	311 (82.9)	64 (17.1)
No	85 (18.5)	12 (14.1)	73 (85.9)

CHB: Chronic hepatitis B; ALT: Alanine aminotransferase.

Table 2 Internal consistency reliability, floor and ceiling effects of the chronic liver disease questionnaire (n = 460) n (%)

Items	Cronbach’sα	Floor and ceiling effects1
		Floor effects	Ceiling effects
Abdominal symptoms	0.80	1 (0.2)	50 (10.9)
Fatigue	0.82	1 (0.2)	1 (0.2)
Systemic symptoms	0.65	2 (0.4)	16 (3.5)
Activity	0.66	1 (0.2)	36 (7.8)
Emotional function	0.90	1 (0.2)	5 (1.1)
Worry	0.85	1 (0.2)	17 (3.7)
Overall	0.83	1 (0.2)	1 (0.2)

¹Floor and ceiling effect: The number and percentage of the chronic hepatitis B patients at the lowest and highest possible scores.

Table 3 Convergent validity and discriminant validity of the chronic liver disease questionnaire (n = 460)

Items	Item-scale correlation (Spearmanγ)
	AB	FA	SY	AC	EM	WO
Abdominal symptoms
1. Abdominal bloating	0.821	0.40	0.42	0.38	0.33	0.22
5. Abdominal pain	0.791	0.41	0.56	0.39	0.35	0.30
17. Abdominal discomfort	0.911	0.52	0.57	0.47	0.46	0.33
Fatigue
2. Tiredness or fatigue	0.46	0.781	0.48	0.42	0.53	0.37
4. Feel sleepy during the day	0.23	0.611	0.30	0.27	0.30	0.23
8. Decreased strength	0.45	0.791	0.50	0.64	0.52	0.41
11. Decreased energy	0.46	0.791	0.50	0.62	0.65	0.42
13. Drowsiness	0.37	0.761	0.43	0.42	0.50	0.31
Systemic symptoms
3. Bodily pain	0.61	0.47	0.711	0.40	0.46	0.33
6. Shortness of breath	0.46	0.50	0.661	0.49	0.42	0.30
21. Muscle cramps	0.35	0.31	0.591	0.36	0.28	0.21
23. Dry mouth	0.32	0.35	0.641	0.26	0.38	0.31
27. Itching	0.35	0.31	0.651	0.29	0.28	0.23
Activity
7. Not able to eat as much as you would like	0.37	0.49	0.35	0.781	0.41	0.28
9. Trouble in lifting or carrying heavy objects	0.41	0.54	0.49	0.841	0.38	0.28
14. Bothered by a limitation of the diet	0.45	0.53	0.43	0.731	0.44	0.28
Emotional function
10. Anxiety	0.36	0.57	0.46	0.43	0.811	0.53
12. Unhappiness	0.34	0.50	0.36	0.39	0.801	0.44
15. Irritability	0.33	0.53	0.42	0.41	0.781	0.43
16. Difficulty in sleeping at night	0.30	0.44	0.39	0.32	0.701	0.33
19. Mood swings	0.36	0.51	0.42	0.35	0.771	0.54
20. Difficulty in falling asleep at night	0.33	0.38	0.40	0.35	0.671	0.35
24. Depression	0.39	0.58	0.48	0.43	0.801	0.58
26. Problems with concentration	0.36	0.54	0.43	0.36	0.731	0.48
Worry
18. Worries about the impact of the liver disease	0.19	0.32	0.30	0.24	0.47	0.781
22. Worries that symptoms will develop into major problem	0.33	0.45	0.38	0.31	0.53	0.891
25. Worries that the condition is getting worse	0.33	0.41	0.38	0.31	0.53	0.881
28. Worries about never feeling any better	0.31	0.39	0.34	0.30	0.50	0.831
29. Availability of a liver for transplant	0.19	0.15	0.24	0.18	0.22	0.352

Convergent validity:

¹The hypothesized item-scale correlations ≥ 0.40;

²correlations < 0.40. Discriminant validity: The hypothesized item-scale correlations are higher than the alternative ones. AB: Abdominal symptoms; FA: Fatigue; SY: Systemic symptoms; AC: Activity; EM: Emotional function; WO: Worry.

Table 4 Factor analysis of the chronic liver disease questionnaire (n = 460)

Items	F 1 (EM)	F 2 (WO)	F 3 (AC + FA)	F 4 (AB + SY)	F 5 (FA)	F 6 (sleep)
Abdominal symptoms
1. Abdominal bloating				0.68
5. Abdominal pain				0.82
17. Abdominal discomfort				0.75
Fatigue
2. Tiredness or fatigue					0.52
4. Feel sleepy during the day					0.75
8. Decreased strength			0.66
11. Decreased energy			0.63
13. Drowsiness					0.72
Systemic symptoms
3. Bodily pain				0.68
6. Shortness of breath				(0.32)
21. Muscle cramps				(0.35)
23. Dry mouth				(0.32)
27. Itching				(0.28)
Activity
7. Not able to eat as much as you would like			0.76
9. Trouble in lifting or carrying heavy objects			0.64
14. Bothered by a limitation of the diet			0.65
Emotional function
10. Anxiety	0.73
12. Unhappiness	0.78
15. Irritability	0.77
16. Difficulty in sleeping at night						0.79
19. Mood swings	0.66
20. Difficulty in falling asleep at night						0.75
24. Depression	0.65
26. Problems with concentration	0.55
Worry
18. Worries about the impact of the liver disease		0.69
22. Worries that symptoms will develop into major problem		0.82
25. Worries that the condition is getting worse		0.81
28. Worries about never feeling any better		0.75
29. Availability of a liver for transplantation		0.51
Eigenvalue	36.14%	7.94%	5.44%	4.57%	4.01%	3.59%
Cumulative	36.14%	44.08%	49.52%	54.09%	58.10%	61.69%

Kaiser-Meyer-Olkin measure of sampling adequacy: 0.929. Bartlett’s test of sphericity: P < 0.001. The items with factor (F) loading coefficient less than 0.45 are written in bracket. EM: Emotional function; WO: Worry; AC: Activity; FA: Fatigue; AB: Abdominal symptoms; SY: Systemic symptoms.

Table 5 Sensitivity of the chronic liver disease questionnaire: scores (mean ± SD) and effect size

Scales	Total (n = 460)	CHB (n = 323)	CHB-related cirrhosis (n = 137)	ES
AB	5.48 ± 1.11	5.59 ± 1.07	5.22 ± 1.16	0.331b
FA	4.76 ± 1.11	4.82 ± 1.08	4.61 ± 1.17	0.19
SY	5.41 ± 0.86	5.54 ± 0.82	5.09 ± 0.87	0.521b
AC	5.45 ± 1.13	5.69 ± 1.03	4.89 ± 1.15	0.711b
EM	4.85 ± 1.10	4.87 ± 1.13	4.80 ± 1.01	0.06
WO	5.06 ± 1.19	5.03 ± 1.23	5.11 ± 1.08	-0.07
Overall	5.17 ± 0.83	5.26 ± 0.83	4.95 ± 0.78	0.371b

¹The effect size (ES) ≥ 0.20. Effect size is calculated as the difference between chronic hepatitis B (CHB) and CHB-related cirrhosis groups mean score divided by the overall standard deviation. Significant difference between CHB and CHB-related cirrhosis groups by independent sample t test:

^bP < 0.01. AB: Abdominal symptoms; FA: Fatigue; SY: Systemic symptoms; AC: Activity; EM: Emotional function; WO: Worry.

Table 6 Sensitivity of the chronic liver disease questionnaire in different alanine aminotransferase results after stratifying the disease

Scales	CHB with ALT test (n = 311)				CHB-related cirrhosis with ALT test (n = 64)
	Total score	Normal (n = 170)	Abnormal (n = 141)	ES	Total score	Normal (n = 29)	Abnormal (n = 35)	ES
Abdominal symptoms	5.59 ± 1.08	5.73 ± 1.04	5.41 ± 1.11	0.301b	5.34 ± 1.16	5.51 ± 1.17	5.20 ± 1.14	0.271
Fatigue	4.81 ± 1.08	4.88 ± 1.09	4.72 ± 1.08	0.15	4.61 ± 1.13	4.75 ± 1.21	4.49 ± 1.06	0.231
Systemic symptoms	5.54 ± 0.83	5.62 ± 0.82	5.44 ± 0.84	0.221	5.17 ± 0.83	5.24 ± 0.83	5.11 ± 0.84	0.16
Activity	5.70 ± 1.03	5.76 ± 1.00	5.62 ± 1.06	0.14	4.94 ± 1.21	5.09 ± 1.30	4.81 ± 1.14	0.231
Emotional function	4.85 ± 1.13	4.94 ± 1.16	4.75 ± 1.09	0.17	4.77 ± 1.06	4.85 ± 1.14	4.71 ± 1.00	0.13
Worry	5.02 ± 1.23	5.10 ± 1.23	4.93 ± 1.23	0.14	4.98 ± 1.20	4.94 ± 1.31	5.01 ± 1.12	-0.06
Overall	5.25 ± 0.84	5.34 ± 0.83	5.15 ± 0.84	0.231a	4.97 ± 0.81	5.06 ± 0.88	4.89 ± 0.74	0.211

¹The effect size (ES) ≥ 0.20. Effect size was calculated as the difference between alanine aminotransferase (ALT) normal and abnormal group mean scores divided by standard deviation of the total score. Significant difference by independent sample t-test between ALT normal and abnormal groups:

^aP < 0.05,

^bP < 0.01.

Table 7 Multiple linear regression analysis (n = 460)

Dependent variable	B	SE	t	P	95%CI
Abdominal symptoms	-0.39	0.12	-3.22	0.001	-0.63, -0.15
Systemic symptoms	-0.23	0.09	-2.63	0.009	-0.41, -0.06
Overall CLDQ	-0.22	0.09	-2.37	0.018	-0.40, -0.04

Independent variable: alanine aminotransferase (normal vs abnormal). The other controlled independent variables were age, gender, marital status, education level, occupation, annual per capita household incomes and the disease [chronic hepatitis B (CHB) and CHB-related cirrhosis]. CLDQ: Chronic liver disease questionnaire.