Laboratory Proficiency TestingAntibodiesDiabetes Mellitus, Type 1Diabetes MellitusDiabetes Mellitus, Type 2Antibody SpecificityAntibodies, ViralAntibodies, BacterialAntibodies, MonoclonalDiabetes ComplicationsAntibody FormationAntibodies, NeutralizingDiabetes Mellitus, ExperimentalAntibody AffinityFluorescent Antibody TechniqueAntibodies, Anti-Idiotypic