Table 1. Association between socio-demographic factors and PHQ-9 scores, the number of somatic symptoms

Characteristic		N (%)	PHQ-9 scores*			Number of somatic symptoms*
			Mean ± SD	t	p-value	Mean ± SD	t	p-value
Sex	Female	252 (73.0)	16.13 ± 5.49	- 1.623	0.106	7.18 ± 2.47	- 1.509	0.132
	Male	93 (27.0)	15.04 ± 5.59			6.73 ± 2.45
Age groups	≤ 40 years	171 (49.5)	16.03 ± 5.53	- 0.636	0.525	7.49 ± 2.47	- 3.208	0.001
	> 40 years	174 (50.5)	15.65 ± 5.55			6.64 ± 2.39
Marital status	Married	222 (64.4)	15.44 ± 5.65	- 1.791	0.074	6.87 ± 2.48	- 1.943	0.053
	Single/Separated	123 (35.6)	16.55 ± 5.27			7.41 ± 2.41
Education	Primary school or under	85 (24.5)	16.71 ± 5.15	1.669	0.096	7.18 ± 2.59	0.497	0.620
	Secondary school or higher	260 (75.5)	15.55 ± 5.63			7.02 ± 2.43
Job status	Executive	129 (37.4)	17.00 ± 5.13	3.048	0.002	6.93 ± 2.48	- 0.759	0.448
	Unskilled/not working	216 (62.6)	15.14 ± 5.66			7.14 ± 2.46
Economic status	Low-income	39 (11.3)	16.95 ± 4.44	1.601	0.115	7.21 ± 2.64	0.387	0.699
	Average or high-income	306 (88.7)	15.70 ± 5.65			7.04 ± 2.45

Using independent T test to compare differences between demographic groups (significant level p < 0.05)