The NAACCR Data Exchange Standard, XML Specifications for Cancer Registry Records, Version 1.4 has been updated on the NAACCR website with clearer examples of how to deal with blank Item values. See Appendix B, Document History, for a description of the revisions.
https://www.naaccr.org/xml-data-exchange-standard/
Thanks
Lori
Lori A. Havener, CTR
Program Manager of Standards
NAACCR