Claims data
Claims data is the record of services billed to insurers: who provided care, where, when and what for. For provider data, it shows where providers actually practice and whom they actually see, rather than what they report.
What's in a claim?
The billing and rendering provider (with NPIs), service location, dates, procedure codes (CPT and HCPCS) and diagnosis codes (ICD-10). Across many payers, claims build a picture of each provider's real activity.
Why use claims to verify provider data?
A provider who billed from an address last month almost certainly practices there. A provider with no claims at a listed location for a long time may have moved. Claims also show which specialties and procedures a provider actually performs.
Limits
Claims lag behind real life by weeks, and they don't cover everything, such as phone numbers or whether a provider is taking new patients. They work best combined with other sources.