Medicare Sample Group Indicator

SAS Name
SAMPLE_GROUP

Medicare 1, 5, or 20% strict sample group indicator.

Comments

CCW creates the sample values using standard CMS processes to identify the random 1, 5, 15, and 20 percent samples of Medicare beneficiaries.

The sample groups are based on a random 20 percent sample that is split into three mutually exclusive groups of 1 percent, 4 percent, and 15 percent. To use the 1 percent sample, specify that SAMPLE_GRP equals “01”.

To use the 5 percent sample, specify that SAMPLE_GRP equals “01” or “04”.

To use the 15 percent sample, specify that SAMPLE_GRP equals “15”.

To use the 20 percent sample, specify that SAMPLE_GRP equals “01”, “04”, or “15”.

Beneficiaries are assigned to sample groups each year based on the last two digits of their Medicare Claim Account Numbers (CANs). Since CANs can change over time (e.g., in the case of remarriage), new beneficiaries are becoming eligible for Medicare, and existing beneficiaries are dying, the sample is cross-sectional. There is no guarantee that the exact same beneficiaries are represented in the same sample group from one year to the next (i.e., this is the strict sampling).

Source: CCW (derived)

01, 04, 15, null/missing (not included in 20% sample for the year)