EPSO from time to time publishes open competitions for scientists and scientific jobs as "Specialist" exams. These always include a Talent Screener in which candidates are required to state their professional background and prove their profile's relevance to the job. Other than that, candidates are still required to go through an Assessment Centre and in most cases they also need to take an abstract, verbal and numerical reasoning test.
The most likely place of employment is in DG Research of the European Commission, or the Joint Research Centre of the Commission, which has offices in several EU countries.
See also:
Specialists | Talent Screener | Assessment Centre | European Commission
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