Describes the strata for which the measure is to be evaluated. There are three examples of reasons for stratification based on existing work. These include: (1) evaluate the measure based on different age groupings within the population described in the measure (e.g., evaluate the whole \[age 14-25\] and each sub-stratum \[14-19\] and \[20-25\]); (2) evaluate the eMeasure based on either a specific condition, a specific discharge location, or both; (3) evaluate the eMeasure based on different locations within a facility (e.g., evaluate the overall rate for all intensive care units and also some strata include additional findings \[specific birth weights for neonatal intensive care units\]).

Grouping defined by important prognostic factors measured at baseline. (ICH E9)

The process of classifying patients into a sequence of grades or ranks as part of the randomization process or for purposes of data analysis.