A reference list is a controlled, well defined vocabulary that can be used in data creation and practice. A reference list may also be referred to as a vocabulary or list of values. Where possible, industry standard lists should be used. Ideally, reference lists are owned and managed by a professional society or standards organization who develops and maintains list on behalf of its members and industry. This volunteer group is compiling lists from both PPDM Association members and other lists from other sources to create a consolidated source for access.