Variables | No. of studies | No. of Total Participants | No. of Cases | OR | 95%CI | Heterogeneity Test | |
---|---|---|---|---|---|---|---|
I2 (%) | P | ||||||
History of headachea | 3 | 741 | 202 | 3.24 | 2.26–4.65 | 0 | 0.47 |
Female gendera | 3 | 741 | 202 | 2.06 | 1.44–2.96 | 0 | 0.40 |
Midbrain lesionsa | 2 | 554 | 107 | 3.56 | 1.86–6.83 | 0 | 0.92 |
Posterior circulation stroke | 1 | 11,523 | 848 | 2.13 | 1.14–4.32 |  |  |