Table 3 subgroup and sensitivity analysis of the effect of GTN on the prevention of PEP

The overall effect of GTN on the incidence of PEP

all forms

7 studies(n = 1814)

0.56 [0.40, 0.79]

3.29

0.001

6.09

0.41

1.4

Different forms

sublingual form

2 studies(n = 260)

0.34 [0.16, 0.75]

2.70

0.007

0.24

0.62

0

transdermal form

3 studies(n = 1266)

0.64 [0.40, 1.01]

1.93

0.05

3.77

0.15

47.0

Different definition of PEP

the same criteria

5 studies(n = 1554)

0.64 [0.43, 0.94]

2.25

0.02

3.80

0.43

0

Sudhindran S

1 studies(n = 186)

0.39 [0.15, 1.00]

Hao JY

1 studies(n = 74)

0.26 [0.06, 1.04]

Different incidence of PEP in the placebo group(10.4% as the cut-off point to stratify the trials)

low incidence

3 studies(n = 1204)

0.75 [0.47, 1.20]

1.22

0.22

1.42

0.49

0

high incidence

4 studies(n = 610)

0.40 [0.24, 0.67]

3.44

0.0006

1.88

0.60

0