Key File

A key file is a file which results from pseudonomizing a data set. It contains personal data elements (e.g. names) and codes with which the occurrences of those names is replaced within the transformed data files. Using key files, data can be re-identified. Hence they should never be stored in the same locations as the research data, and accessibility should be minimized.

Please note: As long as a key file exists, a data set is not anonymized, but pseudonymized. Deleting the key file may render the data set anonymous, but be careful: there might still be identifying elements that prevent the dataset from being truly anonymous.