HMO Indicator

Monthly Medicare Advantage (MA) enrollment indicator.

Historically, most Medicare managed care plans have been health maintenance organizations (HMOs), hence the name of the variable.

This variable indicates whether the beneficiary was enrolled in a Medicare Advantage (MA) plan during a given month. The 01 through 12 at the end of the variable name correspond with the month (i.e., 01 is January and 12 is December).
Code Code value
0 Not a member of HMO
1 Non lock-in, CMS to process provider claims
2 Non-lock-in, group health organization (GHO; MA plan) to process in plan Part A and in area Part B claims
4 Fee-for-service participant in case or disease management demonstration project
A Lock-in, CMS to process provider claims
B Lock-in, GHO to process in plan Part A and in area Part B claims
C Lock-in, GHO to process all provider claims