An LCD, as established by Section 522 of the Benefits Improvement and Protection Act, is a decision by a fiscal intermediary or carrier whether to cover a particular service on an intermediary-wide or carrier-wide basis in accordance with Section 1862(a)(1)(A) of the Social Security Act (i.e., a determination as to whether the service is reasonable and necessary). The difference between LMRPs and LCDs is that LCDs consist only of "reasonable and necessary" information, while LMRPs may also contain category or statutory provisions.

The final rule establishing LCDs was published November 11, 2003. Effective December 7, 2003, CMS's contractors will begin issuing LCDs instead of LMRPs. Over the next 2 years (until December 31, 2005) contractors will convert all existing LMRPs into LCDs and articles. Until the conversion is complete, for purposes of a 522 challenge, the term LCD will refer to both 1.) Reasonable and necessary provisions of an LMRP and, 2.) an LCD that contains only reasonable and necessary language. Any non-reasonable and necessary language a contractor wishes to communicate to providers must be done through an article.