What are Peer-Reviewed, Primary and Empirical Articles?

Lidocaine 2% gel versus lidocaine 4% unpreserved drops for topical anesthesia in cataract surgery. A randomized, double-blind, controlled trial was performed to compare the clinical efficacy of lidocaine 2% gel versus lidocaine 4% unpreserved drops in which the same amount of lidocaine was administered as gel or as unpreserved drops. ................
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