Table 3. Results of Meta-regression for Prevalence among Chinese College Students.

Covariate	Meta-regression coefficient	95%CI	P value	Variance explained (%)
Univariate analyses
Year of publication
2004–2007	0.176	−0.356 to 0.709	0.507	−1.40
2008–2009	0.015	−0.460 to 0.492	0.946	−2.55
2010–2011	0.078	−0.437 to 0.594	0.759	−2.31
2012–2013	−0.281	−0.809 to 0.246	0.288	0.41
Male percent	−0.235	−0.672 to 0.202	0.283	0.46
Sample size
<2000	0.192	−0.258 to 0.642	0.394	−0.64
2000–4000	0.283	−0.168 to 0.734	0.212	1.51
>4000	−0.604	−1.082 to −0.126	0.015	12.16
Area	0.392	−0.077 to 0.863	0.099	4.43
Mean age	−0.230	−0.417 to −0.044	0.017	16.2
Screening tool	−0.435	−0.859 to −0.010	0.045	7.26
Response rate	−0.050	−0.088 to −0.011	0.012	13.01
Medical student	0.359	−0.080 to 0.799	0.106	4.16
Multivariable analyses			0.016	52.85
Response rate	−0.057	−0.10 to −0.014	0.011
Male rate	−0.030	−0.055 to −0.004	0.024
Sample size(2000–4000)	0.778	0.210 to 1.346	0.010