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The German Paediatric Surveillance Unit (ESPED) was founded in 1992 to generate incidence data and detailed clinical descriptions of rare, childhood-onset diseases. Between 1992 and 2017 ESPED completed 96 prospective studies on rare diseases in children. The 3 most frequent clinical entities were: Infectious/communicable disease (n=30), neurological diseases (n = 14) and hematologic diseases (n=10). You can find more on ESPED here.