Describes a possible solution for a user work list associated with a particular subject

foo.xsd

<?xml version="1.0" encoding="UTF-8"?>
<xs:schema targetNamespace="http://foo.edu/schemas"
    xmlns:foo="http://foo.edu/schemas"
    xmlns:xs="http://www.w3.org/2001/XMLSchema"
    xmlns:xnat="http://nrg.wustl.edu/xnat"
    elementFormDefault="qualified"
    attributeFormDefault="unqualified">
    
    <xs:import namespace="http://nrg.wustl.edu/xnat" schemaLocation="../xnat/xnat.xsd"/>

    <xs:element name="WorkList" type="foo:workListData"/>
    
    <xs:complexType name="workListData">
        <xs:annotation>
            <xs:documentation>Creates a work list for the associated subject.</xs:documentation>
        </xs:annotation>
        <xs:complexContent>
            <xs:extension base="xnat:subjectAssessorData">
                <xs:sequence>
                    <xs:element name="tasks" minOccurs="0">
                        <xs:complexType>
                            <xs:sequence minOccurs="0" maxOccurs="unbounded">
                                <xs:element name="Property">
                                    <xs:complexType>
                                        <xs:attribute name="user" type="xs:string" />
                                        <xs:attribute name="state" type="xs:string" />
                                    </xs:complexType>
                                </xs:element>
                            </xs:sequence>
                        </xs:complexType>
                    </xs:element>
                </xs:sequence>
            </xs:extension>
        </xs:complexContent>
    </xs:complexType>
    
</xs:schema>

This is in response to a question on the xnat_discussion group about being able to track work associated with a subject required from particular users. This has not been tested! This would also require some UI work and custom coding on the subject page to allow it to be visible when viewing a particular subject. Refer to the XNAT documentation site for information on creating and installing a custom data type.