Building a national perinatal database without the use of unique personal identifiers

To assess the quality of hospital care, national databases of standard medical procedures are common. A widely known example are national databases of births. If unique personal identification numbers are available (as in Scandinavian countries), the construction of such databases is trivial from a computational point of view. However, due to privacy legislation, such identifiers are not available in all countries. Given such constraints, the construction of a national perinatal database has to rely on other patient identifiers, such as names and dates of birth. These kind of identifiers are prone to errors. Furthermore, some jurisdictions require the encryption of personal identifiers. The resulting problem is therefore an example of Privacy Preserving Record Linkage (PPRL). This contribution describes the design considerations for a national perinatal database using data of about 600,000 births in about 1,000 hospitals. Based on simulations, recommendations for parameter settings of Bloom filter based PPRL are given for this real world application.