title: Mega-aggregation.
authors.forename: Francesco
authors.initials: F
authors.lastname: Carelli
mesh_terms: D005194:Family Practice / Q000458:organization & administration*; D018166:Health Care Reform / Q000458:organization & administration*; D006276:Health Facility Size / Q000458:organization & administration*; D006801:Humans; D007558:Italy; D013222:State Medicine; D006113:United Kingdom