>Inclusion Criteria and Variable Classification:
>Subjects from 0-17 years old were included using a primary search term for diagnosis of “ingested object” from the time period of 2002-2015. Cases of ingested objects were classified as “suspected magnet ingestion” (SMI) if the term “magnet” appeared anywhere in the narrative section of the database.
Where's the screening part you mention? I didn't find anywhere that the inclusion criteria implied that magnets have actually been ingested - or that the results were filtered in any way other than a keyword search.
E.g.: "Child ingested a marble, parent worries that it could have been a magnet" would pass this inclusion criterion.
But i should hope that medical specialists use the abbreviated mri.
Well that's one way to get the magnet out...