Dr. Tad Patrick Callahan, MD
- Medicare services, 2022
- 27
- Part D claims, 2022
- 33
- Industry payments
- $100
- Affiliated sites
- 1
- Medical group
- 1
- Practice address
- 210 S Palisade Dr Ste 101 Suite 101, Santa Maria, CA 93454-5932
- Practice phone
- Call (805) 922-0481
- Professional email
- Get professional email
- Personal email
- Get personal email
- Mobile number
- Get mobile number
Primary practice
Center for Women's Health
Physician office · Santa Maria, California
Find Dr. Callahan's professional email, personal email and mobile number
Dmand AI checks each channel through healthcare-specific waterfall enrichment. See what is on file with a free account, with practice phones, licenses and affiliations.
Dr. Tad Patrick Callahan is an OB-GYN in Redding, California
Dr. Callahan practices at Center for Women's Health in Santa Maria, California.
Dr. Callahan's NPI, 1225112931, was assigned on October 25, 2006. Dr. Callahan graduated from UC Irvine School of Medicine in 1971. Dr. Callahan holds California license A24996.
- NPI
- 1225112931NPI Registry (opens in a new tab)
- NPI enumeration date
- October 25, 2006
- NPI status
- Active
- Practice phone
- (805) 922-0481
- Professional email
- Get email
- Personal email
- Get email
- Mobile number
- Get number
- Sex
- Male
- Estimated age
- 81
- Medical school graduation
- 1971
Sources: NPPES NPI Registry (CMS); Dmand AI Professional Profile Data; and Dmand AI Affiliation Data
Dr. Tad Patrick Callahan practices in Santa Maria and Redding
Dr. Callahan's primary practice is Center for Women's Health, at 210 S Palisade Dr Ste 101 Suite 101, Santa Maria, CA 93454-5932. The practice phone is (805) 922-0481. The NPI Registry lists Dr. Callahan's practice address as 2175 Rosaline Ave, Redding, CA 96001.
- Center for Women's HealthPrimary210 S Palisade Dr Ste 101 Suite 101, Santa Maria, CA 93454-5932Phone(805) 922-0481
- NPI Registry address2175 Rosaline Ave, Redding, CA 96001 · Shasta CountyPhone(805) 922-0481
Sources: NPPES NPI Registry (CMS); Dmand AI Affiliation Data; and Dmand AI Practice Data
Dr. Tad Patrick Callahan is affiliated with 1 site of care and 1 medical group
Dr. Callahan's primary practice is Center for Women's Health in Santa Maria, California. The medical group on file is Presbyterian Medical Group.
Source: Dmand AI Affiliation Data
Dmand AI tracks the EHR system at Dr. Tad Patrick Callahan's practice
Dmand AI tracks the electronic health record (EHR) system at each site where Dr. Callahan practices. Vendor and product names are available with a free account.
| Site | EHR vendor and product |
|---|---|
| Center for Women's Health | Available with a free account |
Source: Dmand AI Technology Install Data
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Dr. Tad Patrick Callahan is one of 4,642 OB-GYNs in California
Obstetrics and gynecology is Dr. Callahan's primary specialty in the NPI Registry, under taxonomy code 207V00000X. Dr. Callahan is board certified in obstetrics & gynecology by the American Board of Obstetrics and Gynecology. Dmand AI has Dr. Callahan's licenses on file in 2 states: California and New Mexico.
Specialties and state licenses
- Obstetrics and gynecology, CaliforniaPrimary
- New Mexico license
Clinical focus
Dmand AI lists menopause and ovarian cyst among the conditions Dr. Callahan treats.
OB-GYNs near Dr. Callahan
Counts of OB-GYNs with a Dmand AI profile, by place and practice. Each opens the list.
Sources: NPPES NPI Registry (CMS); Dmand AI Professional Profile Data; and Dmand AI Peer Benchmarks
Dr. Tad Patrick Callahan billed Medicare for 27 services in 2022
CMS data shows 27 Medicare services from Dr. Callahan across 1 procedure code in 2022, all of them office visits. Medicare paid $1,103 for them. Every service was in an office.
Dr. Callahan's Medicare services by type, 2021 to 2022
- 2021
- 2022
- Office and hospital visits
- 2021: 382022: 2729%
Dr. Callahan compared with the California median for OB-GYNs, 2022
- Dr. Callahan
- California median
- Medicare services
- 27vs 5853% below
- Part D claims
- 33vs 356% below
Medians across 3,823 OB-GYNs in California with Dmand AI profiles that report each measure.
Dr. Callahan's most billed Medicare procedure codes, 2022
CMS publishes codes billed for 11 or more Medicare patients. Each label is the code family; CPT descriptions are licensed by the AMA.
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Medicare shows one payer. Book a meeting to get commercial claims data for Dr. Callahan and other OB-GYNs in California.
Sources: Medicare Physician & Other Practitioners - by Provider and Service (CMS), 2024 data; and Dmand AI Peer Benchmarks
Dr. Tad Patrick Callahan's patients have a median age of 39
Across all payers, Dmand AI patient panel data puts Dr. Callahan's median patient age at 39, with 100% women.
Dr. Callahan's patients across all payers
Dmand AI patient panel data covers Medicare, Medicaid and commercial patients.
Patient panel by age, all payers
Median age 39
Patient panel by sex, all payers
- Women100%
- Men0%
Source: Dmand AI Patient Panel Data
Dr. Tad Patrick Callahan wrote 33 Medicare Part D claims in 2022
In 2022, Dr. Callahan wrote 33 Medicare Part D claims. They cover 2 drugs, with $3,686 in total drug cost. In 2021, CMS named 49 claims across 3 drugs.
Dr. Callahan's most prescribed drugs by claims, 2022
CMS names a drug when it has 11 or more claims. Share is of the claims for drugs CMS names.
Part D claims for drugs CMS names, 2021 to 2022
- 2021
- 2022
- Claims for drugs CMS names
- 2021: 492022: 3333%
Drugs named by CMS: 2 in 2022, 3 in 2021.
Source: Medicare Part D Prescribers - by Provider and Drug (CMS), 2024 data, released May 6, 2026
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Dr. Tad Patrick Callahan received $100 in industry payments in 2019
CMS Open Payments shows 1 general payment to Dr. Callahan from 1 drug or device company in 2019. Food and beverage make up the largest share, 100% of the total. Merck Sharp & Dohme Corporation paid the most, $100.
Companies that paid Dr. Callahan the most, 2019 to 2019
Share is of all general payments to this clinician.
Source: Open Payments (CMS), 2025 data, released July 7, 2026
Dr. Tad Patrick Callahan graduated from UC Irvine School of Medicine
Dr. Callahan graduated from UC Irvine School of Medicine in 1971.
- Medical school
- Board certified in obstetrics & gynecology
Source: Dmand AI Professional Profile Data
Dr. Tad Patrick Callahan accepts plans from 5 insurance carriers
Dr. Callahan is in network with 5 carriers, including Elevance, Cigna and HCSC. Medicare plans come from the most carriers, 5. Check the plan with the practice before a visit.
- Elevance
- Cigna
- HCSC
- Blue Cross Blue Shield of Massachusetts
- Regence Health Plans
Plan types Dr. Callahan accepts, by number of carriers
- Medicare5
- PPO5
- HMO3
- EPO1
- POS1
Source: Dmand AI Insurance Network Data
Sources for Dr. Tad Patrick Callahan's profile data
| Data on this page | Source |
|---|---|
| NPI, name, sex, specialty and licenses | NPPES NPI Registry (CMS) (opens in a new tab)Dmand AI Professional Profile Data |
| Practice locations and phone | NPPES NPI Registry (CMS) (opens in a new tab)Dmand AI Affiliation DataDmand AI Practice Data |
| Primary practice, affiliations and health system | Dmand AI Affiliation Data |
| Medicare services and procedure codes | Medicare Physician & Other Practitioners - by Provider and Service (CMS) (opens in a new tab) |
| State medians for the same specialty | Dmand AI Peer Benchmarks |
| Medicare patients and the all-payer patient panel | Dmand AI Patient Panel Data |
| Part D prescribing | Medicare Part D Prescribers - by Provider and Drug (CMS) (opens in a new tab) |
| Industry payments | Open Payments (CMS) (opens in a new tab) |
| Training, board certification and memberships | Dmand AI Professional Profile Data |
| Insurance carriers and plan types | Dmand AI Insurance Network Data |
| EHR at each practice site | Dmand AI Technology Install Data |
| Similar physicians | Dmand AI Affiliation Data |
Data last refreshed October 2026Report an inaccuracyRemove my information
FAQ
Frequently asked questions about Dr. Tad Patrick Callahan
Spotted something out of date? Email hello@dmand.ai and we will check the record. Contact details live in the free trial.
What is Dr. Tad Patrick Callahan's NPI number?
Dr. Tad Patrick Callahan's NPI number is 1225112931. It was assigned on October 25, 2006, and it is active in the NPI Registry.
What kind of doctor is Dr. Tad Patrick Callahan?
Dr. Tad Patrick Callahan is an OB-GYN in Redding, California. The primary specialty in the NPI Registry is Obstetrics & Gynecology Physician (taxonomy code 207V00000X).
Where does Dr. Tad Patrick Callahan practice?
Dr. Callahan practices at 210 S Palisade Dr Ste 101 Suite 101, Santa Maria, CA 93454-5932. Dr. Callahan also practices at 2175 Rosaline Ave, Redding, CA 96001. Dr. Callahan's primary practice is Center for Women's Health in Santa Maria, California.
What is Dr. Tad Patrick Callahan's office phone number?
The practice phone on file for Dr. Callahan is (805) 922-0481.
What is Dr. Tad Patrick Callahan's medical license number?
Dr. Callahan holds California license A24996, one of the licenses on file in 2 states.
Which states has Dr. Tad Patrick Callahan been licensed in?
Dmand AI has state licenses on file for Dr. Callahan in California (1972 to 2026) and New Mexico (2023 to 2026).
What medical group is Dr. Tad Patrick Callahan part of?
Dr. Callahan is linked to Presbyterian Medical Group.
Does Dr. Tad Patrick Callahan accept Medicare?
Yes. CMS data shows Dr. Callahan billed Medicare for 27 services in 2022.
Is Dr. Tad Patrick Callahan board certified?
Yes. Dr. Callahan is board certified in obstetrics & gynecology by the American Board of Obstetrics and Gynecology.
What services does Dr. Tad Patrick Callahan bill to Medicare?
In 2022, Dr. Callahan's most billed Medicare services were office visit, established patient (99212).
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Where did Dr. Tad Patrick Callahan go to medical school?
Dr. Callahan graduated from UC Irvine School of Medicine in 1971.
What drugs does Dr. Tad Patrick Callahan prescribe most?
In 2022 Medicare Part D data, Dr. Callahan's most prescribed drugs by claims were Estradiol and Estradiol (Twice Weekly).
Has Dr. Tad Patrick Callahan received payments from drug or device companies?
CMS Open Payments shows $100 in general payments to Dr. Callahan from 1 company from 2019 to 2019. The largest total came from Merck Sharp & Dohme Corporation.
How long has Dr. Tad Patrick Callahan been practicing?
Dr. Callahan graduated from medical school in 1971, 55 years ago.
What insurance does Dr. Tad Patrick Callahan accept?
Dr. Callahan is in network with 5 carriers, including Elevance, Cigna and HCSC. Medicare plans come from the most carriers, 5. Check the plan with the practice before a visit.
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