What is Marielys Then's NPI number?

Marielys Then's National Provider Identifier (NPI) is 1457205536, a unique 10-digit ID issued by CMS for use in standard healthcare transactions.

What is Marielys Then's specialty?

Marielys Then is listed in the NPPES registry with a primary specialty of Mental Health Counselor (Behavioral Health & Social Service Providers).

Where is Marielys Then located?

Marielys Then's practice location on file with NPPES is 125 Hartwell Ave, Lexington, MA 02421-3100.

What is Marielys Then's phone number?

The practice phone number listed in the NPPES registry for Marielys Then is (781) 861-0890.

Is Marielys Then's NPI active?

Yes — Marielys Then's NPI (1457205536) is active in the NPPES registry as of the last update on 2026-02-24.

IndividualActive

Marielys Then

NPI 1457205536 · Mental Health Counselor · Lexington, MA

Marielys Then is a Mental Health Counselor provider in Lexington, MA (NPI 1457205536).

Provider details

NPI number: 1457205536
Entity type: Individual
Primary specialty: Mental Health CounselorBehavioral Health & Social Service Providers
Sex: Female
Sole proprietor: Yes

Specialties & taxonomies

Mental Health CounselorPrimary101YM0800X
Behavioral Health & Social Service Providers

Profile Score

Basic profile(47/100 index)

A profile completeness & documented-activity index — NOT a quality, outcomes, or patient-satisfaction rating.

Registry tenure38% of score
Under 1 yr in registry
Profile completeness38% of score
83% of core fields populated
Practice footprint23% of score
1 documented practice location

Signals a provider has no public data for (e.g. Medicare claims) are left out of the score entirely — never counted as zero — so providers without that data are not penalized. See the full formula and weights in our methodology.

Practice location

125 Hartwell Ave

Lexington, MA 02421-3100

Phone: (781) 861-0890

Street-level locationGet directions

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Mailing address