How we weigh sources
Last checked 2026-09-24.
Every material claim on BeautyEvidence is one of four kinds, and each page says which: product evidence, technology research, a manufacturer claim, or unknown. The kinds are never merged. A study about a type of device is not evidence about a particular model, and a brand's marketing is not a finding.
The four kinds of claim
| Kind | What it is | What it can support |
|---|---|---|
| Product evidence | A record about this exact model: its FDA 510(k) or listing, its manual, its specification sheet, its retail listing's stated contents. | What the model is, what it includes, what it is cleared or specified for. |
| Technology research | Published studies or reviews about a kind of device. | What is known about the technology in general, never about one model's results. |
| Manufacturer claim | What a brand says about its own product. | Only that the brand says it; it is quoted and attributed. |
| Unknown | Anything no source we read settles. | Nothing. It is shown as unknown, not filled by inference or resemblance. |
What we never do
- Test products or present a score as a measurement.
- Give medical, dermatological or personal advice, or say a device suits your skin or hair.
- Treat an FDA 510(k) clearance as approval or as proof that a device works.
- Carry a claim from one model, size or generation over to another.
Dates
Each comparison shows the date its facts were last checked. That date changes only when the sources are re-read; a change to the page's layout does not move it.