This is the ValueSet that contains all the codes in AllowedSignature signatureFormat (https://profiles.ihe.net/QRPH/CCG/ValueSet/ccg-signature-sigformat) and AllowedSignature signatureFormat (https://profiles.ihe.net/QRPH/CCG/ValueSet/ccg-signature-sigformat). E.g. what you have to deal with if you get resources containing codes in either of them