National immunisation recommendations: why country-specific evidence and context matter.

National Immunisation Technical Advisory Groups (NITAGs) are independent expert groups issuing recommendations on the introduction and use of licensed vaccines in national programmes. They consider both context-free evidence - safety, efficacy, effectiveness - and country-specific aspects, including local epidemiology, cost-effectiveness, societal values, and programmatic feasibility. Several policy developments in the European Union (EU), including EU-level joint clinical assessments under the new Health Technology Assessment regulation and non-binding recommendations by the European Centre for Disease Prevention and Control, reflect a desire to reduce duplication of efforts but also a push towards harmonisation of immunisation recommendations across countries. Using the German NITAG as an example, we illustrate that identical clinical evidence can legitimately yield different national recommendations. Even though equitable access to vaccines across countries is desirable, fundamental differences in country-specific context limit harmonising national immunisation schedules. International collaboration and supra-national guidance can support but not substitute for national, context-sensitive public health decision-making.