<qa>  How many EDTA-blood tubes will be drawn during the first routine blood sampling?Step 1. All eligible patients in the emergency department or the neurological ward will be evaluated for enrollment into the study. On admission, 2 x 7.5ml- EDTA-blood tubes will be drawn during the first routine blood sampling, and 2 x 7.5ml-EDTA-blood tubes on the following routine blood-sampling. Copeptin levels will be assessed in a blinded batch analysis upon completion of the plasma asservation. Measurement will be performed with a new chemiluminescence sandwich immunoassay. 