In Germany, there has been no population-level pharmaco-epidemiological study on the safety of the Covid-19 vaccines. One factor preventing such a study so far relates to challenges combining the different relevant data bodies on vaccination with suitable outcome data, specifically statutory health insurance claims data. Individual identifiers used across these data bodies are of unknown quality and reliability for data linkage. As part of a larger pharmaco-vigilance study on the COVID-19 vaccines, called RiCO (German "Risikoevaluation der COVID-19-Impfstoffe", Englisch "Risk assessment of COVID-19 vaccines"), a feasibility study is being conducted to determine the overall confidence level with which existing data can be analysed in relation to the safety of the COVID-19 vaccine. This RiCO feasibility study will establish a dataflow combining claims data and vaccination data for a sub-sample of the total German population, describe data quality for each data set from the various sources, estimate the proportion of the different linkage errors and will develop various approaches for linking the data in addition to the simple form of linkage using a common identifier in order to reduce possible linkage errors. These last three points are the core objective of the feasibility study. A secondary objective is to test the viability of the required dataflow involving multiple stakeholders from different parts of the healthcare system. Results will be published and used to plan the actual pharmaco-vigilance study on the COVID-19 vaccines for Germany, as well as future research on the role of COVID vaccines as risk or protective factors for long-term COVID-19 effects.

The authors have declared no competing interest.

The study is funded by the German Federal Ministry of Health.

I confirm all relevant ethical guidelines have been followed, and any necessary IRB and/or ethics committee approvals have been obtained.

Yes

The details of the IRB/oversight body that provided approval or exemption for the research described are given below:

In accordance with national legal requirements (Paragraph 75 of Book X of the Social Security Code, SGBX), permission to use of the statutory health insurance claims data was requested and granted by the national regulatory authority for statutory health insurances. The vaccination data will be used in accordance with the requirements of Paragraph 3 of the national regulation on COVID-19 vaccinations (Verordnung zum Anspruch auf Schutzimpfung und auf Praeexpositionsprophylaxe gegen COVID-19 (COVID-19-Vorsorgeverordnung). This regulatory framework permits the use of these pseudonymised data bodies without individual consent. Ethical approval was also not required for this secondary data study and was therefore not sought.

I confirm that all necessary patient/participant consent has been obtained and the appropriate institutional forms have been archived, and that any patient/participant/sample identifiers included were not known to anyone (e.g., hospital staff, patients or participants themselves) outside the research group so cannot be used to identify individuals.

Yes

I understand that all clinical trials and any other prospective interventional studies must be registered with an ICMJE-approved registry, such as ClinicalTrials.gov. I confirm that any such study reported in the manuscript has been registered and the trial registration ID is provided (note: if posting a prospective study registered retrospectively, please provide a statement in the trial ID field explaining why the study was not registered in advance).

Yes

I have followed all appropriate research reporting guidelines, such as any relevant EQUATOR Network research reporting checklist(s) and other pertinent material, if applicable.

Yes

The data used for the present study are not available for further use.