Cultural Validation of the Chinese Central Sensitization Inventory in Patients with Chronic Pain and its Predictive Ability of Comorbid Central Sensitivity Syndromes

Figures & data

Table 1 Participant Characteristics

		Value
Sex, n (%)	Male	39 (16.60)
	Female	196 (83.40)
Age (years)	Mean (SD)	64.2(9.53)
BMI	Mean (SD)	24.2(4.08)
Employment, n (%)	Employed	68 (28.94)
	Unemployed	79(33.62)
	Retired	82(34.89)
	Others	6 (2.55)
Musculoskeletal pain classification	-Neuropathic	72(30.60)
	-Nociceptive	132(56.20)
	-Mixed	31(13.20)
Duration of pain (years)	Mean (SD)	4.2(5.04)
CSI total score	Mean (SD)	36.4(13.10)
Average pain intensity	Mean (SD)	5.7(1.50)
Maximal pain intensity	Mean (SD)	7.3(1.67)
EQ-5D index	Mean (SD)	0.6(0.15)
Anxiety score	Mean (SD)	6.3(3.66)
Depression score	Mean (SD)	6.4(3.91)

Abbreviations: BMI, body mass index; CSI, central sensitization inventory; EQ-5D, EuroQol-5D; SD, standard deviation.

Figure 1 Distribution of severity levels of central sensitization.

Table 2 Correlations Between CSI and Clinical Symptoms

Variable	Correlation Coefficient	p value
Duration of pain	−0.074	0.258
Pain intensity	0.188	0.004
EQ-5D index	−0.375	<0.001
Anxiety	0.525	<0.001
Depression	0.467	<0.001

Abbreviations: CSI, central sensitization inventory; EQ-5D, EuroQol-5D.

Table 3 Factor Loading of the Exploratory Factor Analysis

Item Number	Item Topic	F1	F2	F3	F4	F5	Not Loading
1	Unrefreshed in the morning	0.270	0.179	0.277	0.090	−0.048	X
2	Muscle stiff/achy	0.624	−0.176	0.180	−0.077	0.033
3	Anxiety attacks	0.121	−0.077	0.766	−0.075	0.066
4	Grind/clench teeth	0.070	−0.059	−0.016	0.457	0.178
5	Diarrhea/constipation	0.014	0.055	0.086	0.150	0.193	X
6	Need help with daily activities	0.222	0.277	0.096	0.022	0.099	X
7	Sensitive to bright lights	0.249	0.133	−0.182	0.056	0.593
8	Easily tired with physical activity	0.444	0.339	0.061	−0.117	0.038
9	Pain all over body	0.781	−0.005	−0.113	0.276	−0.163
10	Headaches	0.280	0.042	0.336	0.048	−0.010	X
11	Bladder/urination pain	−0.083	−0.091	0.183	0.543	0.220
12	Do not sleep well	0.054	0.393	0.309	−0.138	0.016	X
13	Difficulty concentrating	−0.293	0.780	0.102	0.094	0.096
14	Skin problems	−0.072	0.111	−0.020	0.322	0.131	X
15	Stress makes symptoms worse	0.066	0.140	0.384	0.260	−0.063	X
16	Sad or depressed	−0.055	0.152	0.802	0.010	−0.113
17	Low energy	0.281	0.706	−0.046	−0.022	−0.047
18	Tension in neck and shoulder	0.651	−0.006	0.017	−0.186	0.269
19	Pain in jaw	0.124	−0.200	0.145	0.251	0.284	X
20	Certain smells make dizzy	0.031	0.168	0.069	0.247	0.110	X
21	Urinate frequently	−0.149	0.184	0.027	0.010	0.484
22	Restless legs	0.211	0.230	0.086	0.088	0.004	X
23	Poor memory	−0.038	0.495	−0.121	0.137	0.199
24	Trauma as a child	−0.047	0.145	−0.075	0.556	−0.069
25	Pelvic pain	0.329	−0.002	−0.103	0.366	−0.142	X

Notes: The values in bold indicate the item meets the requirement for factor loading (significance threshold of 0.40). X means the item is not loading.

Table 4 Diagnoses of Central Sensitivity Syndromes

	Number (%)
Diagnoses
Restless leg syndrome	0
Chronic fatigue syndrome	2 (0.85)
Fibromyalgia	3 (1.28)
Temporomandibular joint disorder	1 (0.43)
Migraine or tension headache	18 (7.66)
Irritable bowel syndrome	16 (6.81)
Multiple chemical sensitivities	0
Neck injury (including whiplash)	5 (2.13)
Anxiety or panic attack	20 (8.51)
Depression	44 (18.72)

Table 5 CSI-C Scores Between Participants with and without Central Sensitivity Syndrome

Category	CSI-C Total Score Mean (SD)	95% CI
No CSS (n=204)	35.5 (12.93) *	(33.74–37.31)
1 CSS (n=24)	40.7 (12.51)	(35.39–45.95)
2 and above CSSs (n=7)	48.3 (13.33) *	(35.96–60.61)

Note: *Represents significant difference between “No CSS” group and “2 and above CSSs” group.

Abbreviations: CSS, central sensitivity syndrome; CSI-C, Chinese version of central sensitization inventory; SD, standard deviation; CI, confidence interval.

Figure 2 Receiver operating characteristic curve.