Sir,

We appreciate the interest of Sergentanis and Chatziralli in our published manuscript, ‘Lack of positive effect of intravitreal bevacizumab in central serous chorioretinopathy: meta-analysis and review.’1 They have addressed methodological issues concerning meta-analysis because the SD of difference was not provided in the manuscript.

We absolutely agree that it would have been more meaningful meta-analysis if we contacted the authors of each study, asking them to calculate de novo the difference as Sergentanis and Chatziralli have rightly pointed out. Alternatively, Hedges g formula for pooled SD was used to estimate difference SD. And then, paired SD was calculated, as follows, pooled SD × sqrt(2 × 1−r)).

Although our meta-analysis failed to verify the positive effect of IVB in CSC, the outcome of this treatment is still unknown owing to many limitations, such as small sample sizes, clinical heterogeneity, and methodology. Therefore, further investigation including more studies with larger scales and better methodologies will help to clarify the uncertain relationship between CSC and IVB.