Response to: Comment on “Pain Perception of the First Eye versus the Second Eye during Phacoemulsification under Local Anesthesia for Patients Going through Cataract Surgery: A Systematic Review and Meta-Analysis”

With high levels of heterogeneity, meta-analyses would have low predictive values no matter what the I2 values are [7]. [...]we only did a subgroup analysis on the four studies that did not use any sedatives/analgesics. [...]we thank Sun et al. for their interest in our study and for offering their valuable opinion and perspective from an anesthetist’s angle. [6] R. Ursea, M. T. Feng, M. Zhou, V. Lien, R. Loeb, "Pain perception in sequential cataract surgery: comparison of first and second procedures," Journal of Cataract & Refractive Surgery, vol. 37 no. 6, pp. 1009-1014, DOI: 10.1016/j.jcrs.2011.01.020, 2011.