Factual error: When the TARDIS is flying over London at the beginning, the London Eye is visible. It's supposed to be 1996, and the Eye was built later than that, for the new millennium celebrations. (00:00:30)
Factual error: When the Doctor spots Rory taking a photo of Prisoner Zero, we're shown a brief close-up of Rory's hospital identity badge. The date of issue is given as "30/11/1990". The main body of the episode is set in 2008, two years before Rory and Amy's wedding in 2010. It's further established in the episode that Rory and Amy played together as children after her first meeting with the Doctor in 1996, with Rory observing that Amy made him dress up as the Raggedy Doctor. Rory could not possibly have worked for the hospital for eighteen years at the time of the episode. (00:33:10)
Suggested correction: Continue watching the show as this is a clue and not a mistake. In later episodes Rory becomes the Last Centurion who watches over Amy for over 1,800 years while she is in the Pandorica. So while Rory was born in 1989, because of time travel and events that occurred to him, he's lived long enough to work at the hospital since 1990.
Bishop73
At that stage, Rory had not time-traveled at all. If he had been working at the hospital since 1990, he would have been a baby. And it was shown in "The Big Bang" that he works as a guard in the Museum where the Pandorica is kept in the alternate timeline, not at the hospital.