Methodology and Data Considerations
We collected all relevant claims from December 2020 to August 2021 (the most recent month as of when this blog was written) by selecting HCPCS codes for COVID-19 vaccines as below:
- 0001A: Pfizer-BioNTech Covid-19 Vaccine Administration – First Dose
- 0002A: Pfizer-BioNTech Covid-19 Vaccine Administration – Second Dose
- 0011A: Moderna Covid-19 Vaccine Administration – First Dose
- 0012A: Moderna Covid-19 Vaccine Administration – Second Dose
- 0031A: Janssen (Johnson & Johnson) Covid-19 Vaccine Administration
When pulling out those relevant claims, we also extracted the first vaccination date and the second date (if it exists) for each beneficiary, and the vaccine brand associated with each date. In theory, a fully vaccinated beneficiary should have HCPCS codes that refer to only one brand, and each corresponds to “first dose” and “second dose”.
There are cases where the first/second dose HCPCS code appears twice for some beneficiaries. With the current data access, it would not be possible to determine the cause of the data hygiene issue. However, as the first dose and second dose of the Pfizer or Moderna COVID-19 vaccine should be exactly the same, both chemically and from a dosage standpoint,3 we consider such beneficiaries to be fully vaccinated, and assign the dates chronologically to be the first shot date and the second shot date.
After cleaning the data, we linked those vaccine records with the annual enrollment information from CMS to count the total number of fully/partially vaccinated, and the remaining considered to be part of the no vaccine claims group.
It can be noted that the overall vaccination rate is relatively low compared to the national vaccination rate, and we think this could be due to the reasons below:
- Many people may walk into vaccination sites without registering insurance information, as the vaccine is free regardless of insurance status. For reference, HRSA (Health Resources and Services Administration) announces that it has paid over 5 million claims to health care providers for administering COVID-19 vaccines to uninsured individuals.4 Some of those claims could have been people who did not register insurance information when receiving COVID-19 vaccines. As a result, although shots are given, such records would not be found in the Medicare claims.
- People in the no vaccine claims group may have other sources, other than CMS, to pay for the vaccines. As a result, no records would be available in Medicare claims.
Although the total counts may not 100% accurately reflect our nation’s commitment and efforts in providing access to COVID-19 vaccines, our analysis still sheds light into important questions, such as the role of ACO enrollment, how distressed communities react compared to others, and the major players in giving vaccine shots. Further analysis should be carried in comparison with the official data from CDC to understand the gap between Medicare claims and the national vaccination rates.
Overall, as of August this year, 35.31% of the Medicare beneficiaries have received at least one vaccine shot, and 30.72% of the Medicare beneficiaries are fully vaccinated (including the Johnson & Johnson one shot vaccine). The full vaccination rate also varies greatly across US geographies, and is likely related to different levels of access to healthcare, presence of ACO enrollment, and community distress scores. We will discuss these breakdowns in more detail in later sections of this blog.