Thank you for your question. The measure developers have worked on harmonization of guidance language in the metadata and for the clinical trial participant exclusion language, many of the eligible hospital measures now have this statement: Denominator Exclusion guidance: "The exclusion for patients who are clinical trial participants is limited to patients participating in a clinical trial for the same conditions as covered by the measure. Other clinical trials are not valid reasons for exclusions." Some of the measures have kept the language more specific (such as CMS30) based on the steward’s requirements for those particular measures. The clinical trial participant value set only has one code in it, because there are not codes for each specific trial, which is the reason for adding the guidance in the metadata. To request a new SNOMED CT code for each type of clinical trial is prohibitive, as new trials get added frequently and it would also make it very difficult to keep the clinical trial participant value sets up to date.

EH - CMS171v3 - Guidance says "The exclusion for patients who are clinical trial participants is limited to patients participating in a clinical trial for the same conditions as covered by the measure. Other clinical trials are not valid reasons for exclusions.". But the corresponding logic and ValueSet doesn't support this requirement. The ValueSet 2.16.840.1.113883.3.526.2.643 of April 2013 contains only one value "Clinical trial participant (person)". This means, all clinical trial participants will be excluded, not just those covered by this measure. I see a clarification on this in the April 2013 Release Notes for CMS30. But I do not see similar clarification for CMS171. Can you please clarify whether the same clarification as in CMS30 applies to CMS171 and others as well in Apr 2013, regarding clinical trials?