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“The linkage of different individual-level health data with the aim of creating a common data set is called record linkage. Research institutes, cancer registries, hospitals or health insurance companies may collect health data on one and the same person, but if these different records of one person cannot be linked, important research questions must remain unanswered”, emphasizes Prof. Dr. Wolfgang Ahrens, head of the department Epidemiological Methods and Etiological Research at Leibniz Institute for Prevention Research and Epidemiology – BIPS. He adds: “It is only by linking different data sources that scientific questions can be investigated that could not be addressed with one data source alone because of the limited scope of variables. These linked data unleash a huge potential for health research to improve prevention, therapy and care of the population. Because these health data are sensitive, they are protected against potential misuse by stringent legislation.”
For this reason, NFDI4Health has developed a white paper on record linkage with other experts, including, among others, the Medical Informatics Initiative and the University Medicine Network. This paper describes the obstacles to the effective use of health data and makes suggestions on how the linkage of health data at the person level can be improved in Germany. The focus is on practicable solutions that are in line with the European General Data Protection Regulation.
“The current legal environment severely restricts the use of valuable health data for research. Record linkage in Germany is particularly hampered by the fact that, unlike countries such as Denmark, there is no unique personal identifier that would allow health information to be merged across different data bodies without having to transmit identity data such as name and address”, explains Dr. Sebastian C. Semler, executive director of the Technology, Methods, and Infrastructure for Networked Medical Research e.V. (TMF e.V.). He continues: “In addition, there is no infrastructure in Germany that would allow comprehensive record linkage across studies and data bodies in a secure environment. Until now, time-consuming individual case solutions have had to be found in each case to link data records in research. Often, attempts at record linkage fail due to the lack of clear research-friendly regulations. Thus, record linkage in Germany falls far short of the standards in other European countries.”
To counter this, the white paper describes various use cases that illustrate the current technical and legal hurdles and calls for cross-border and low-bureaucracy solutions. In particular, the white paper recommends that legislators introduce a unique identifier, establish domain-specific pseudonyms, establish a central oversight and approval authority, and establish a decentralized federated research data infrastructure.
NFDI4Health is part of the National Research Data Infrastructure (NFDI) funded by the federal and state governments. NFDI4Health aims to build a comprehensive inventory of German epidemiological, public health and clinical trial data. The collection and analysis of these data are essential for the development of new therapies, comprehensive care approaches and preventive measures. Personal health data require special protection. The declared goal of NFDI4Health is therefore to combine security and usability. The consortium is composed of an interdisciplinary team of 17 partner institutions. In addition, 48 renowned institutions from the health sector are involved; letters of support have been received from 37 international institutions.
