<xs:schema xmlns="http://www.rixg.org.uk/" xmlns:xs="http://www.w3.org/2001/XMLSchema" targetNamespace="http://www.rixg.org.uk/">

<xs:simpleType name='BloodRhesus'>
    <xs:annotation>
        <xs:documentation>See https://www.datadictionary.nhs.uk/data_dictionary/attributes/p/person/person_rhesus_factor_de.asp</xs:documentation>
    </xs:annotation>
    <xs:restriction base="xs:string">
        <xs:enumeration value="POS">
            <xs:annotation>
                <xs:documentation>RhD-Positive (does have the Rh D antigen)</xs:documentation>
            </xs:annotation>
        </xs:enumeration>
        <xs:enumeration value="NEG">
            <xs:annotation>
                <xs:documentation>RhD-Negative (does not have the antigen)</xs:documentation>
            </xs:annotation>
        </xs:enumeration>
    </xs:restriction>
</xs:simpleType>

</xs:schema>