B18zip Apr 2026

B18ZIP serves as the member zipcode field, identifying the beneficiary’s geographic location at the time of the HOS baseline survey.

HOS measures how well Medicare Advantage plans help beneficiaries maintain or improve their health. The geographic information provided by B18ZIP helps in longitudinal studies tracking the same individuals over a two-year period. B18zip

The 2015-2017 Cohort 18 Baseline was conducted using version 3.0 of the HOS survey. B18ZIP serves as the member zipcode field, identifying

It is classified as a "character" (text) field to preserve leading zeros in ZIP codes. The 2015-2017 Cohort 18 Baseline was conducted using

The Medicare HOS program, including the Cohort 18 Baseline survey, is managed by CMS and used to assess plan performance, as detailed in the resdac.org/cms-data/files/hos-rif - ResDAC HOS documentation. If you are working with HOS data, I can help you with:

Understanding how HOS data is used for Star Ratings. Background: The history of Medicare HOS cohorts. Let me know what specific information you need next! hos_dug_c18b.pdf - HOSonline.org

The data is pulled from Medicare Advantage Organization (MAO) member records in the 2015 Cohort 18 Baseline RIF (Research Identifiable File) and LDS (Limited Data Set). Role in Medicare HOS