Physician Profile
Unclaimed ProfileAbout JANSSEN
Based in O Fallon, MO, David Alan Janssen, M.D. is listed in the NPI registry under infectious disease. David graduated from Indiana University School of Medicine in 1988. David is also listed as specializing in specialist. Medicare claims data shows David provided 571 services to 193 patients.
Summarised automatically from public NPI registry and CMS Medicare data. Not written or reviewed by this provider. Claim this profile to replace it.
Education & Training
Areas of Expertise
Licensing & Certification
Source: NPPES NPI Registry
Contact Information
- (636) 344-2014
- Email not available
Practice Locations
20 PROGRESS POINT PKWY STE 206
O Fallon, MO 63368
Procedures Most Often Billed to Medicare
571 services · 193 patients · 5 distinct codes
| Procedure | Type | Code | Services |
|---|---|---|---|
| Subsequent hospital care with moderate levelof medical decision making, if using time, at least 35 minutes | Office visit | 99232 |
394 |
| Initial hospital care with moderate level of medical decision making, if using time, at least 75 minutes | Office visit | 99223 |
62 |
| Established patient office or other outpatient visit with moderate level of decision making, if using time, 30 minutes or more | Office visit | 99214 |
52 |
| Subsequent hospital care with straightforward or low level of medical decision making, per day, if using time, at least 25 minutes | Office visit | 99231 |
33 |
| Subsequent hospital care with moderate levelof medical decision making, if using time, at least 50 minutes | Office visit | 99233 |
30 |
Source: CMS Medicare public data. Shows how often procedures were billed — not quality of care or patient satisfaction.
Related providers
Connections drawn from the registry and from what providers have told us. A link here is not a referral or an endorsement.
Also at this address 4
Providers at the same street address. Each files their own registry entry, so a shared practice often appears under several different names.
Trained at Indiana University School of Medicine 8
Other providers in the same specialty who trained at the same institution.
Class of 1988 at Indiana University School of Medicine 8
Providers who graduated from the same medical school in the same year.
Common questions
What does Dr. Janssen specialize in?
Dr. Janssen is an infectious disease in O Fallon, MO. This is the primary taxonomy recorded against the NPI in the federal registry, listed there as “INFECTIOUS DISEASE”.
NPI registry
Where is Dr. Janssen located?
Dr. Janssen is listed at 20 PROGRESS POINT PKWY STE 206, O Fallon, MO 63368. Addresses come from the NPI registry and can lag a move, so confirm before travelling.
NPI registry
What is Dr. Janssen's phone number?
The number on file is (636) 344-2014. Guide.md cannot book appointments or pass on messages — please call the office directly.
NPI registry
What is the NPI for Dr. Janssen?
Dr. Janssen's National Provider Identifier is 1700995339. It is issued by the Centers for Medicare & Medicaid Services and is unique and permanent — it does not change if they move practice.
NPI registry
Where did Dr. Janssen go to medical school?
Dr. Janssen attended Indiana University School of Medicine, graduating in 1988. This comes from the CMS National Downloadable File.
CMS public data
How much experience does Dr. Janssen have?
Dr. Janssen has 38 years experience. Calculated from a graduation year of 1988, reported in the CMS National Downloadable File.
CMS public data
What does Dr. Janssen do most often?
According to Medicare billing data, Dr. Janssen the Medicare record under this individual NPI shows mainly office visits and diagnostic testing. Hospital-based physicians usually have their procedural work billed by the facility rather than under their own number, so this is a floor on their practice, not a description of it. This reflects Medicare patients only and is billing volume, not a measure of quality.
Medicare claims
Is Dr. Janssen's profile verified?
Not yet. This profile is built from public federal data and has not been confirmed by Dr. Janssen. If this is you, claiming it is free.
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Claim this profileProvider data sourced from the NPPES NPI Registry and CMS public datasets. Information is provided for reference and is not medical advice.