Table 2.

Meta-regression of factors correlated with seroprevalence among children 1–5 years of age.

Characteristic	Number of estimates	β coefficient	95% CI
Total	98	0.002	(0.001, 0.003)**
Age
1 year	25	ref
2 years	21	0.083	(0.002, 0.164)*
3 years	20	0.226	(0.142, 0.310)**
4 years	20	0.312	(0.230, 0.395)**
5 years	12	0.386	(0.285, 0.487)**
Sampling year
2008 or before	23	ref
2009	15	−0.176	(−0.315, −0.037)*
2010	42	0.186	(0.012, 0.360)*
2011 or after	18	0.261	(0.092, 0.431)**
Sampling method
Random sampling	62	ref
Physical examination	9	−0.437	(−0.573, −0.302)**
Unknown	27	−0.227	(−0.310, −0.145)**
Assay method
ELISA	18	ref
NTA	80	0.067	(−0.030, 0.164)
Seasonality
Season	46	ref
Non-season	17	−0.045	(−0.152, 0.062)
Unknown	35	0.082	(−0.061, 0.225)
Epidemic region
North	10	ref
South	84	−0.203	(−0.376, −0.029)*
Published language
Chinese	60	ref
English	38	−0.133	(−0.213, −0.053)**

^*p < 0.05;

^**p < 0.01.

I² = 79.9% (95%CI, 72.0–85.9%; p < 0.001). QM (df=15) = 240.80; p < 0.001.