Michelle Nguyen, MD
As reported to Medicare
- Credential
- MD
- Primary specialty
- Gastroenterology
- Medical school graduation
- 1998
- Medical school
- University of Michigan Medical School
- National Provider Identifier (NPI)
- 1811967920
Total number of colonoscopies this clinician billed to Medicare in the most recent 12-month claims period, according to CMS.
Percentile rank of 53 colonoscopies compared to other clinicians with a primary specialty of Gastroenterology, Internal Medicine, Family Practice, or General Practice who have billed Medicare for at least one colonoscopy in the same period.
The figures above reflect only procedures that this clinician billed to Medicare, according to CMS. Therefore, they may not reflect the total number of procedures this clinician performed during the 12-month reporting period. See Understanding CMS Data below.
Source: Centers for Medicare & Medicaid Services (August 18, 2026 release).
Michelle Nguyen's Colonoscopy Billing Volume Compared to Peers
Reading the curve: find a volume along the bottom, and the line gives the percentile of clinicians with a primary specialty of Gastroenterology, Internal Medicine, Family Practice, or General Practice at or below it. The marked point is this clinician. The shaded block covers the 2,250 clinicians CMS reports as 1-10, because CMS suppresses counts below 11. The axis runs from 0 to 1,598, the highest count CMS reports in the group, and gives low counts more room than high ones so the whole range fits. The labels under the axis mark the 25th percentile, the median and the 75th percentile.
Source: Centers for Medicare & Medicaid Services (August 18, 2026 release).
| Percentile | Colonoscopies billed to Medicare |
|---|---|
| 20th | 20 |
| 30th | 35 |
| 40th | 51 |
| 50th | 70 |
| 60th | 90 |
| 70th | 116 |
| 80th | 150 |
| 90th | 212 |
| Highest | 1,598 |
Previous data releases
CMS refreshes this data "on a quarterly basis, as technically feasible." The table shows this clinician's figures from each CMS data release.
| CMS data release | Colonoscopies billed | Percentile rank |
|---|---|---|
| August 18, 2026 Current | 53 | 41% |
| August 11, 2026 Prior | 53 | 41% |
| June 26, 2026 Prior | 37 | 38% |
About these releases. Each release counts procedures over what CMS describes as "a one-year observation window, with a lookback beginning three months prior to the present day", allowing three months for claims to be submitted and processed. CMS does not publish the start and end dates of the window behind any release, and consecutive releases may cover overlapping periods, or the same period with later-arriving claims added.
Understanding CMS Data
CMS's "Colonoscopy" category combines specific billing codes for colonoscopy to calculate the number of times each clinician billed Medicare for a "Colonoscopy." These include screening colonoscopy, diagnostic colonoscopy, and colonoscopy with biopsy or polyp removal. CMS's list also includes flexible sigmoidoscopy and laparoscopic appendectomy, so a clinician's count may include those procedures. CMS counts one procedure per patient per day, so a colonoscopy that included both a biopsy and a polyp removal counts once. CMS reports only procedures that clinicians billed to Original Medicare and Medicare Advantage. Therefore, CMS's procedure volume data does not include procedures that clinicians may have performed on patients who have other health care coverage (e.g., commercial insurance, self-pay, or the VA). Billing variation and coding errors can also affect CMS's data. Therefore, the number of procedures that CMS reports for a clinician may be higher or lower than the actual number of colonoscopies a clinician performed during the reporting period. Lastly, only clinicians with a primary specialty of Gastroenterology, Internal Medicine, Family Practice, or General Practice (as reported to Medicare) are presented.
National Percentile Calculation
CMS publishes its own percentile for this data using a single, national pool that also includes clinicians with other primary specialties, such as General Surgery, Colorectal Surgery, Physician Assistant and Nurse Practitioner. We use CMS's percentile formula, but restrict the comparison group to clinicians with a primary specialty of Gastroenterology, Internal Medicine, Family Practice, or General Practice, so our number answers a narrower question: how does this clinician's procedure volume compare with other clinicians who billed Medicare for at least one colonoscopy and reported one of those as their primary specialty?