Table 2 Summary of the mean difference, sensitivity/specificity and sROC analyses of ophthalmic artery Doppler parameters for overall, mild and severe pre-eclampsia

PR

0.24 (0.14 a 0.35)

n = 3 studies [12, 13, 30]

0.21 (0.11 a 0.30)

n = 4 studies [11, 14, 32, 33]

0.35 (0.32 a 0.37)

n = 4 studies [11, 14, 32, 33]

0.84 (0.77 a 0.89)

n = 6 studies [13,14,15, 30, 32, 33]

0.08 (0.02 a 0.25)

n = 6 studies [13,14,15, 30, 32, 33]

0.885

n = 6 studies [13,14,15, 30, 32, 33]

P2

9.67 (3.91 a 15.43)

n = 4 [12, 13, 15, 30]

3.62 (0.93 a 6.31)

n = 2 [15, 33]

4.26 (0. 39 a 8.14)

n = 2 [15, 33]

0.85 (0.68 a 0.94)

n = 4 [13, 14, 30, 33]

0.12 (0.06 a 0.23)

n = 4 studies [13, 14, 30, 33]

0.926

n = 4 studies [13, 14, 30, 33]

RI

-0.07 (-0.10 a -0.03) n = 7 studies [12, 13, 16, 15, 17, 18, 20]

-0.02 (-0.14 a 0.09)

n = 7 studies [11, 14, 15, 19, 31,32,33]

-0.12 (-0.14 a -0.09)

n = 6  studies [11, 13, 15, 31,32,33]

0.76 (0.69 a 0.82)

n = 7 studies [12,13,14,15, 30, 32, 33]

0.21 (0.15 a 0.28)

n = 7 studies [12,13,14,15, 30, 32, 33]

0.833

n = 7 studies [12,13,14,15, 30, 32, 33]

PI

-0.48 (-0.59 a -0.38) n = 4 studies [12, 13, 15, 30]

-0.62 (-0.88 a -0.37)

n = 7 [11, 14, 15, 19, 32,33,34]

-0.87 (-1.20 a -0.55)

n = 6 studies [11, 14, 15, 32,33,34]

0.74 (0.66 a 0.80)

n = 5 studies [13, 14, 30, 32, 33]

0.20 (0.11 a 0.33)

n = 5 studies [13, 14, 30, 32, 33]

0.794

n = 5studies [13, 14, 30, 32, 33]

PSV

1.65 (-3.39 a 6.69)

n = 4 studies [12, 13, 15, 30]

-0.36 (-3.32 a 2.60)

n = 4 studies [11, 14, 15, 33]

1.51 (-3.67 a 6.69)

n = 4 studies [11, 14, 15, 32]

0.55 (0.37 a 0.72)

n = 3 studies [13, 14, 30]

0.46 (0.29 a 0.64)

n = 3 studies [13, 14, 30]

0.556

n = 3 studies [13, 14, 30]

EDV

3.06 (0.79 a 5.34)

n = 4 studies [12, 13, 15, 30]

2.37 (0.62 a 4.12)

n = 4 studies [38, 40, 44, 46]

4.47 (1.27 a 7.66)

n = 4 studies [11, 14, 15, 33]

0.77 (0.62 a 0.87)

n = 4 studies [13, 14, 30, 3]

0.33 (0.22 a 0.46)

n = 4 studies [13, 14, 30, 33]

0.772

n = 4 studies [13, 14, 30, 33]