Table 1. Summary of the diagnostic results of the included studies.

study	Year	Country	Simple size		Simple type		Test methods	TP (n)	FP (n)	FN (n)	TN (n)	Cut-off Values (pmol/L)
			Cases	Controls				a	b	c	d
Hellstrom	2010	USA	79	56	Urine	/	ELISA	70	5	9	51	NR
Macuks	2012	Riga	23	55	Urine	/	ELISA	18	14	5	41	1300
Jian HQ	2012	China	30	78	Urine	Serum	ELISA	28	1	2	77	71.519
Yuan ZF	2012	China	50	78	Urine	Serum	ELISA	40	7	10	71	6.51
Zhang YJ	2013	China	98	57	Urine	Serum	ELISA	84	7	14	50	18.74
Wang Y	2014	China	41	62	Urine	Serum	ELISA	28	4	13	58	6.51
Liao	2015	USA	92	187	Urine	/	ELISA	47	10	45	177	Specificity of 95%

Abbreviations: ELASA, Enzyme Linked Immunosorbent Assay; TP, true positive rate; FP, false-positive rate; FN, false-negative rate; TN, true negative rate; NR, not reported;