Factual error: When Major Kira was introducing Lieutenant Commanders Dax and Worf to the arriving Trill scientists, she introduces them as Commander Dax and Worf. While in informal conversation, they could be addressed as Commander, when making formal introductions, the person making the introductions would use their full proper rank. This is an error that no ranking officer would make, especially not twice. (00:03:10)
Suggested correction: And when was this established? If you are basing this error on modern American military protocols, there is no reason Starfleet in the 24th century would follow the same rules and traditions.
Yes, although it's not just American military introductions, it's pretty standard in most militaries to use full rank when making formal introductions, which has been followed for the most part by the writers, with other introductions that have happened onscreen.