## Sources
Every published figure comes from a public, primary source: a government survey, a federal agency, a professional association's research or a systematic review. Each book's *Sources and Method* appendix lists every source with the date it was read. Vendor blogs and trade-press figures without a checkable method aren't used as evidence.
Where no primary source exists, the book says so. *The Inactive Patient List*, for example, found no public study of how many inactive dental patients return when a practice reaches out, so every return rate in it is labelled an assumption.
## The four number labels {#labels}
Every figure in a Press book is one of these kinds, and it's labelled where it appears.
Published
From a public, primary source, printed with its year. Figures that change often are also kept on a dated web page, because a printed page can't keep up.
Composite
Invented for a composite practice (such as Kestrel Park Family Dental). The practice, its staff and its patients aren't real. Its fees, counts and hours are plausible, not measured.
Synthetic
Computed from composite inputs by a formula printed in the book. Every one can be reproduced with the free calculator, and each is rechecked against a set of hand-worked cases before an edition goes out.
Assumption
A figure we had to choose because nothing better exists yet, such as a return rate. Always set in bold, with a note on what will replace it and when.
A fifth kind, **observed**, is reserved for results measured in a real practice and recorded with a date and a reviewer. There are none yet, and the books don't pretend otherwise.
## Evergreen in print, perishable on the web
Books carry principles, formulas, decision rules and plans. Anything that goes out of date goes on a dated web page instead: laws and regulations, consent rules, payer terms, software click-paths, prices and benchmark tables. Each of those pages carries the date it was last reviewed and, where the topic needs one, the name of a qualified reviewer. Pages about consent, calling and texting rules or privacy won't go up until that reviewer has read them.
## AI use {#ai}
Each book states how AI was used, on its copyright page. For *The Inactive Patient List*, the author used AI tools in drafting parts of the text and in producing the illustrations; every chapter was directed, checked and edited by the author, and every figure traces to a public source or to a labelled composite input. The statement in the book is meant to match what's declared to the retailer at upload. If the two ever differ, the retailer declaration is corrected, and this page says so.
## Corrections {#corrections}
When we find an error, or a reader reports one, the fix goes on the book's companion page under *Errata and updates*, with the date, where it was, what it said and what it says now. Material corrections are also noted in The Letter. The next edition carries the fix. Corrections aren't made silently.
## Professional advice
The books offer business and operational guidance. They aren't legal, clinical, tax or accounting advice. Diagnosis, treatment and recall intervals belong to the treating clinician; questions of law belong to a qualified attorney.
## Patient data
No tool on this site asks for patient-identifiable information, and none should be given one. The calculators take totals and run entirely in your browser.
## Affiliates and conflicts of interest {#conflicts}
- **The author owns Alchemy Inside,** a consulting practice for cash-pay med spas. *The Med Spa Money Map* was first published under the Alchemy Inside name, and its tools live on that site. Alchemy Inside is listed on [Services](/services/) with this disclosure. Service prices never appear in Press books.
- **No affiliate links today.** If the Press ever earns a commission from a product or service it mentions, the link will say so where it appears, and this policy will list the relationship.
- **No paid placement.** Nobody pays to be mentioned in a book or on this site.
## Who writes the books
The books are written by [Bill Eisenhauer](/about/), an engineer. He isn't a dentist or a clinician and doesn't write as one. Chapters that touch clinical or regulatory ground are sent to a qualified reviewer before publication.