Table 2 Various descriptions of the level of de-identification as encountered in the reviewed documents

“your data is anonymous”

“requested data have been made (fully) anonymous”

“you cannot be recognized by it (removal of full name and address)”

“your data will be shared in such a way that the data cannot be traced back to you”

“your identification will be removed”

“use without revealing your identity”

“that it is unlikely that anyone will be able to identify you”

“identification of the individual is not reasonably possible”

“if full anonymization is not possible, data is de-identified to the fullest extent possible to ensure data is unidentifiable”

“you will only be identified by a number”

“you will be given a special code that identifies you”

“data is issued without directly identifiable patient numbers”

“data is issued with unique pseudonyms as patient identifiers”