Table 3 Summarized results of the meta-analysis

All combined

15

0.85(0.81–0.88)

0.69(0.60–0.77)

0.89(0.81–0.94)

6.2(4.0-9.7)

0.35(0.27–0.43)

18(12–27)

0.85

98%

Subgroup analysis

Threshold value(ng/mL)

<12

9

0.90(0.87–0.92)

0.65(0.49–0.77)

0.92(0.87–0.95)

8.3(5.9–11.7)

0.38(0.27–0.55)

22(16–29)

1.00

96%

12–30

6

0.78(0.74–0.81)

0.75(0.68–0.81)

0.80(0.65–0.90)

3.8(2.0-7.1)

0.31(0.24–0.41)

12(5–27)

0.45

86%

Recruit patients

Outpatient

10

085(0.81–0.88)

0.69(0.55–0.81)

0.88(0.75–0.94)

5.6(2.9–10.6)

0.35(0.24–0.51)

16(9–30)

0.66

98%

Hospitalized or Emergency

5

0.89(0.86–0.92)

0.68(0.63–0.72)

0.91(0.90–0.93)

7.9(6.6–9.5)

0.35(0.31–0.41)

22(17–30)

0.70

100%

Measurement method

Enzyme*

3

0.90

0.81(0.74–0.88)

0.82(0.77–0.86)

5.7(2.3–13.9)

0.23(0.12–0.44)

29(6-145)

0.67

NA

Chemiluminescence

7

0.88(0.85–0.90)

0.72(0.65–0.78)

0.89(0.86–0.92)

6.7(5.1–8.6)

0.32(0.26–0.39)

21(16–28)

1.00

67%

Progesterone supplement

Yes

9

0.83(0.79–0.86)

0.71(0.62–0.78)

0.87(0.78–0.93)

5.5(3.3-9.0)

0.34(0.28–0.41)

16(11–25)

1.00

97%

No or unclear

6

0.88(0.85–0.91)

0.69(0.48–0.84)

0.91(0.78–0.97)

7.9(3.4–18.2)

0.34(0.20–0.60)

23(10–55)

0.53

96%

Out of China

No

10

0.86(0.82–0.89)

0.66(0.52–0.78)

0.91(0.82–0.96)

7.6(4.0-14.4)

0.37(0.26–0.52)

21(11–37)

0.69

98%

Yes

5

0.84(0.80–0.87)

0.74(0.65–0.81)

0.82(0.74–0.89)

4.2(2.9–6.1)

0.32(0.24–0.41)

13(8–21)

1.00

76%

Follow up (weeks)

≤20

9

0.89(0.86–0.92)

0.72(0.66–0.78)

0.90(0.87–0.92)

7.1(5.8–8.6)

0.31(0.25–0.38)

23(18–30)

1.00

76%

>20

6

0.80(0.76–0.83)

0.63(0.40–0.81)

0.87(0.61–0.96)

4.7(1.8–12.0)

0.43(0.28–0.66)

11(5–23)

0.96

98%