How search works, and what a classification is.
Filters combine as an and, every one of them has a not, and the single most useful thing to understand is the difference between a classification and a specialisation — because getting that wrong is how a list comes back short.
Classification and specialisation
A specialty is filed in two levels. The classification is the broad heading — internal medicine, dentist, nurse practitioner, psychologist. The specialisation is one kind of practice beneath it — cardiology and endocrinology sit under internal medicine, orthodontics under dentist, family practice under nurse practitioner.
Asking for a classification matches every specialisation beneath it. That is almost always what somebody means by “all of internal medicine”, and it has a second advantage: when a new specialisation is added to the reference list, a classification filter already includes it, while a hand-ticked list of specialisations silently does not.
Asking for a specialisation returns only that one. Use it when the product or the message is genuinely for that practice and nobody else — and expect a much smaller list, which is the point.
The trap is the other direction. A word that sounds like a heading is often a specialisation: endocrinology is not a classification, it is a specialisation under three different ones. Typing it into the search box works, because free text is matched against every level and returns the people who filed it. Typing it into a classification filter does not, because nothing is filed under that name as a heading.
What you can narrow on
Filters are combined with an and: every one you add makes the list smaller. Each also has an exclusion twin, so you can ask for a state and not a specialty, or a specialty and not an employer, without building two lists and subtracting them by hand.
| Family | What it covers |
|---|---|
| Who they are | Identifier, first and last name, organization name, individual or organization, active or inactive, and when the identifier was issued. Active only, unless you ask otherwise. |
| Where they practise | State, city, ZIP, street, or a radius in miles around a ZIP — which is how to cover a catchment that does not respect a county line. |
| What they practise | Classification, specialisation, the raw taxonomy code, and the credential letters they filed. |
| How reachable they are | Whether a work email exists, the trust tier it has to clear, whether the employer has a website domain. |
| Who they work for | Employer, billing group, health system, the certified facilities they are affiliated with, and the record system a practice runs where that is evidenced. |
| Standing and programmes | Federal programme exclusions, opt-out and revocation flags, and the programme participation a record carries. |
| Facility attributes | Facility type, certified beds, published star ratings, chain and ownership — for the organizations rather than the people. |
What search will never return
A record somebody has asked us to suppress is not in the results, and a suppressed value on a record that is otherwise public is withheld rather than blanked. Both are covered on the suppression page.
A quarantined email address is never counted as an address, whatever the trust filter is set to — including when it is set to any. Why an address ends up quarantined is on the trust tiers page.
Contact details are never in a public result. Public pages carry the public record: name, identifier, credentials, specialty, practice location and the practice phone as filed.
Counting before you commit
Every filtered search reports a total before you export anything, and the list pages publish counts per specialty and per state — records, how many carry a work email, how many carry a trusted-tier one, how many carry a practice phone — without an account. That is the cheapest way to find out whether your segment is worth buying, and it is deliberately readable by anyone.
Questions
What is the difference between a classification and a specialisation?
A classification is the broad heading a specialty is filed under; a specialisation is one kind of practice beneath it. Asking for a classification matches every specialisation under it, and keeps doing so when a new one is added to the reference list.
Why did my specialty filter return nothing?
Usually because the word is a specialisation rather than a classification, or the other way round. Endocrinology, for instance, is a specialisation under three separate classifications. Typing it into the search box works, because free text is matched against every level.
Do filters combine as and or or?
As and: each filter you add narrows the result. Where a filter takes several values — several states, several classifications — those values are an or among themselves, which is what you want.
Can I exclude something?
Yes. Every criterion has an exclusion twin, so you can ask for one thing and not another in a single query rather than building two lists and subtracting.
Does a search include inactive providers?
No, not unless you ask for them. The default is active records only, which is what almost everybody wants; retired and deactivated identifiers are available when the question is specifically about them.
Can I search by distance rather than by state?
Yes. Give a ZIP and a radius in miles and the search covers everything inside it, which is how to describe a catchment or a territory that does not follow state or county lines.
Other help pages
- Reveals
- What a reveal is, what it costs, when it is free, and why a refused reveal is never counted.
- Plans and limits
- The four things every plan meters, how to see what you have left, and what happens when one runs out.
- Email trust tiers
- What trusted, probable, doubtful and rejected mean, and what an unscored address counts as.
- Suppression and removal
- How an opt-out is applied everywhere, why nothing is deleted, and how someone gets removed.
- API keys
- Scopes, the per-minute pace, the monthly quota, the headers that report both, and where the reference is.
- Exports and append
- What lands in a file, how rows are counted, how your own file is matched, and how files are marked.
- Accounts and sign-in
- Seats and invitations, two-step sign-in, signing other sessions out, and who can change billing.
- Home address and cell
- The contracted product: how it is matched, what the confidence score means, and where it never appears.