You require a PIN if you wish to use a telematics infrastructure app, for example if you want to have medical data stored on your TK eHealth card. The PIN protects your data from being read without authorisation.
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For the electronic medical record you require the PIN if you choose the login option with a NFC-compatible smartphone, eHealth card and PIN.
Medical data is not read when the card is simply inserted in the card reader, for example at the doctor’s surgery. The PIN for the current card also has to be entered. You decide whether and which items of medical information are stored on or with the card.