Table 1.

Demographic characteristics of included participants (N = 1,178).

	Total	Clinical medicine	Stomatology	Cohen's d or Spearman's rho	P-value
Number of students	1,178	722	456	–	–
Academic year
Grade 1	240	143	97	–	–
Grade 2	250	154	96	–	–
Grade 3	235	138	98	–	–
Grade 4	226	139	87	–	–
Grade 5	227	148	79	–	–
Age (years)	21.1 ± 1.7	21.2 ± 1.7	21.0 ± 1.7	0.12	0.12
BMI	21.1 ± 2.6	21.1 ± 2.6	21.1 ± 2.5	0	0.65
Gender				0.09	0.002
Male	553	365 (50.6%)	188 (41.3%)
Female	625	357 (49.4%)	268 (58.7%)
Ethnicity				0.006	0.83
Han	1,156	709 (98.2%)	447 (98.0%)
Others	22	13 (1.8%)	9 (2.0%)
Drinking				0.09**	0.001
Non-drinker (0 g/d)	981	620 (85.8%)	361 (79.1%)
Mild drinker (0.1–9.9 g/d)	59	35 (4.8%)	24 (5.2%)
Moderate drinker (10.0–29.9 g/d)	80	46 (6.3%)	34 (7.4%)
Heavy drinker (30.0–49.9 g/d)	58	21 (2.9%)	37 (8.1%)
Severe drinker (>50.0 g/d)	0	0 (0%)	0 (0%)
Smoking				0.001	0.33
0 cigarette/d (non-smoker)	1,160	711 (98.5%)	449 (98.5%)
0–5 cigarettes/d	11	8 (1.1%)	3 (0.7%)
5–10 cigarettes/d	4	2 (0.3%)	2 (0.4%)
10–15 cigarettes/d	2	0 (0%)	2 (0.4%)
15–20 cigarettes/d	0	0 (0%)	0 (0%)
>20 cigarettes/d	1	1 (0.1%)	0 (0%)

^**Correlation is significant at the 0.01 level (2-tailed).