This literature review was carried out in the context of a participatory policy-making process to support the contents of the upcoming Swiss National Immunisation Programme (NIP). The interpretation of this evidence is, therefore, embedded into a deliberative process which extends for several months and which includes immunisation stakeholders of several constituencies. The deliberative process is the backbone of policy-making and assesses the relevant evidence through several mechanisms: (a) deciding which interventions are suitable in the Swiss context; and (b) the magnitude of effects that can be expected.
A total of 10,719 references were retrieved: 4,585 primary research studies (PRS) and 6,134 systematic reviews (SR). A large proportion of these references were judged as irrelevant (e.g. studies of vaccine efficacy, vaccine development or animal studies). As a result, 22 PRS from Switzerland or neighbouring countries and 18 SR worldwide were included. Interventions addressed information, vaccine prescription, new vaccination programmes, information and vaccination campaigns, organisational interventions, financial incentives, and combinations of the above.
• All types of interventions have examples of modest effects, or no effects or even negative effects on vaccination coverage.
• Information-related interventions have been the most widely reported. At least one review showing promising findings dealt with mass media.
• Educational interventions targeting users showed very modest effects except for a single study (educational intervention involving health care staff).
• The most effective ways of delivering vaccinations were those more proactive, such as campaigns or approaching parents in wards.
• Organisational interventions were the least reported albeit with promising findings.
