Exploring flexible methods for national health examination surveys in Germany

BACKGROUND: National health examination surveys (HES) are rarely carried out due to high costs and high complexity. We piloted more flexible methods such as self-sampling, self-measurements and household visits conducted by a study-nurse replacing physician examinations in study centers. METHODS: Feasibility of several new methods for the German HES was tested, e.g.: large-scale implementation of unattended self-sampled dried blood spots (DBS) and oral-nasal swabs (ONS) in a countrywide general population panel including a large subsample with migration background (Study 1, n = 15,122); household visits with brief biosampling & examinations (Study 2, n = 470); and unattended blood pressure (BP) self-measurements with mailed devices and video instructions (Study 3, n = 202). RESULTS: Among participants consenting to participate, Study 1 showed successful postal self-sampling of DBS for SARS-CoV-2 antibody tests in 98% of participants and 97% valid ONS for SARS-CoV-2 PCR tests. Study 2 showed successful standardized measurements of BP (97%), weight/height (99%) and DBS and venous blood sampling with onsite whole blood centrifugation (97%). Temperature requirements for centrifugation, cooled transport and ATC-coded medication assessment (Anatomical Chemical Classification) proved challenging and needed revised methods to avoid data loss. Nested validation studies confirmed use of a multiplex assay for various antibodies with DBS and of HbA1c analysis with uncooled specimen. The strict and time-consuming BP self-measurement-protocol with 12 measurements in Study 3 was followed only by 54% of participants. CONCLUSIONS: Self-sampling and biosampling & examinations in households are feasible options for HES but protocols with high complexity may result in low data completeness.