Linkage with external sources
Boost your research by linking the Lifelines data to data collected or registered elsewhere. For example, to verify self-reported illnesses or self-reported drug treatments with medical or pharmacy registries, or to add more detailed information about participants’ employment history or causes of death.
Linkage of Lifelines data is possible if the purpose of the project fits with the aim of Lifelines (research on healthy ageing, in line with the informed consent signed by our participants) as well as the aim of the other data source(s). In addition, best practices regarding the protection of sensitive personal data protection must be followed, using measures such as irreversible pseudonymization, encryption of data, use of trusted third parties (TTPs), and controlled data access.
Currently available linkage possibilities
Individual level data
- Statistics Netherlands (CBS) Microdata (e.g. data on employment history, cause of death and many other registries)
- Palga (Dutch pathology database, e.g. for tissue/biopt-based cancer or IBD diagnoses)
- NKR (Dutch cancer registry)
- IADB.nl or Pharmlines (Prescribed medication data)
- NIVEL (Netherlands institute for health services research, e.g. primary care data)
- Perined (Perinatal Registry of the Netherlands)
- Coming soon: AHON (General practitioner database Northern Netherlands)
Environmental data
(linked to participants’ historical and current home addresses)
- GECCO (Environmental exposure data, e.g. air pollution, food environment)
- CBS Microdata (e.g. data on neighborhood characteristics)
- LISA (Dutch database on retail outlet locations)
Please note: Individual level linkages are typically done using a trusted third party, to minimize the risk of data breaches. Lifelines uses the services of ZorgTTP (linkage with Palga or NKR) or Statistics Netherlands (IADB, NIVEL).
Experience of: Melisa Castañeda Vanegas (Palga/IKNL)
"As researchers, we are blessed to have this Lifelines data available to us so easily. The Lifelines workspace is also great, because you can constantly update your data when your research needs change."
Experience of: Eelko Hak, Pharmlines (IADB)
In 2017, Lifelines partnered with the Groningen Research Institute of Pharmacy (GRIP) to launch the PharmLines Initiative. This initiative allows Lifelines data to be linked to data on medicines dispensed by community pharmacies. The initiative is possible through a collaboration with the InterAction Data Base (IADB.nl). This is a database with detailed information on dispensed drugs, including information about the patient and the physician who prescribed the drug. The link between data from Lifelines and IADB.nl makes more research possible, for example on the effects and risks of taking certain drugs.
Experience of: Carel-Peter van Erpecum (LISA)
Dr. Carel-Peter van Erpecum (Epidemiology, UMCG) used Lifelines data linked with the LISA register to investigate the effect of food environment on obesity among the northern Dutch population. This study showed that the proximity of fast food restaurants may influence the increase in obesity. Obesity is one of the biggest public health challenges: the percentage of Dutch adults who are overweight has increased from 33% in 1981 to 50% in 2022. Van Erpecum's research is highly relevant for policy makers working on public living space.
How does it work?
Just like for regular Lifelines projects, you start a linkage project by submitting an application. After discussing the linkage procedures and arranging the required agreements and approvals, you will get access to the Lifelines data via our Lifelines Workspace. Once you have prepared your dataset for linkage, our Data Managers will arrange that this dataset is uploaded to the TTP, by which it will be linked to the data from the external data source. The linked datasets are usually not released via a Lifelines Workspace. For linkages via CBS, you can access the linked data through the CBS Remote Access Environment. For linkages via ZorgTTP, linked data can often be accessed through a Workspace hosted by the UMCG.
For certain linkages, standard linkage procedures are already in place (see the list above). A new research project requiring one of these linkages can therefore be started when approval from all parties is arranged by the researcher, and, when necessary, contracts between Lifelines and the linkage partner and/or TTP are in place (arranged by Lifelines). If a project requires a linkage that is not yet in the list, please contact the Lifelines Research Office. There are many possibilities and we can give you an estimate on the timeline and the costs.
Some points of attention
- Many of the external data sources mentioned above require that you apply for their data directly with them. The researcher is responsible for this. It is not possible to request these data in your Lifelines application.
- Be aware that external data sources may not cover all Lifelines participants. For example, IADB.nl currently has prescription data for approximately 50% of Lifelines participants.
- The same goes for linkages that go the other way around: if you would like to link your research cohort from the Northern Netherlands to Lifelines, the expected coverage would be approximately 10% (since Lifelines roughly included 10% of the population of the northern part of the Netherlands).
Costs
Several factors are of influence on the total costs of a linkage project. For Lifelines, the costs for a new research project including linkage via ZorgTTP are € 5,450 (excl. VAT). This includes 6 months use of a Lifelines workspace, in which you can prepare the Lifelines dataset that you want to link to the external datasource. For linkages via CBS, the costs are € 4,000 (excl. VAT). Please be aware that these costs do not include the costs for the acting TTP (ZorgTTP or CBS). The external datasource that you would like to link with may also charge a fee for data access, which is not included in the fee mentioned above.
Ready to start?
Submit an application
