This section (negation pattern) is not about removing patients from a measure population but rather how to represent: Absence of evidence for a particular event Documentation of an event not occurring together with a reason The information that concerns the commenter is captured in the measure's definition. such as an exclusion criteria. Will clarify the text: propose: "The negation patterns described here are about approaches for identifying when events are not present or when events are documented as not occurring for a reason. These patterns may appear throughout a measure in any of the various population criteria, depending on measure intent. For example, the absence of a particular medication may be grounds for membership in the initial population, denominator, numerator, or an exclusion or exception criteria, depending on how the measure is constructed."