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The original article on “Comparison of Dexamethasone–Dimenhydrinate and Dexamethasone–Ondansetron in Prevention of Nausea and Vomiting in Postoperative Patients” published online in December 2016 suggested that the effect of the dexamethasone–dimenhydrinate combination was superior to the effect of the dexamethasone–ondansetron combination for postoperative nausea and vomiting [1].

It was a great pleasure to read this article; however, a discrepancy has been noticed.

The authors stated that the study groups were randomly designed as two groups. One group had dexamethasone 8 mg iv and dimenhydrinate 1 mg/kg iv postoperatively. The other group had dexamethasone 8 mg iv and ondansetron 4 mg iv postoperatively.

However, in the data collection section, the authors stated that all patients were treated with ondansetron 4 mg iv to relieve the symptoms of postoperative nausea and vomiting.

Due to study design, one arm was supposed to take ondansetron 4 mg iv. But the authors clearly reported that all patients had this medication. This would make it impossible to study the effect of ondansetron over dimenhydrinate because, according to their report, both arms also had ondansetron 4 mg iv.