# How we test

The scoring model, the panel protocol, what disqualifies a product outright, and what we do when we have not tested something ourselves.

- **Canonical:** https://www.30plusskin.care/how-we-test
- **Site:** 30+/SKIN — Skincare, published as a spec sheet.
- **Issue:** ISSUE NO. 12 / REV. 2026.08
- **Standing terms:** INDEPENDENT · AFFILIATE-FUNDED · NOT MEDICAL ADVICE

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## The scoring model

| Criterion | Weight | What it measures |
| --- | --- | --- |
| EVIDENCE FOR THE ACTIVE | 30% | Does the published literature support this molecule at this concentration for this claim? Graded A–C, same scale as the evidence register. |
| FORMULATION INTEGRITY | 20% | Working pH inside the active's window, a vehicle that permits penetration, and packaging that does not oxidise the contents. |
| DISCLOSURE | 15% | Are concentrations published? Is the full INCI available before purchase? Are claims quantified or is it all 'up to'? |
| TOLERANCE IN USE | 15% | Panel-reported irritation, stinging and flaking across the trial window, against a vehicle-only control arm. |
| TEXTURE & WEAR | 10% | Absorption, residue, pilling under sunscreen or make-up. The reason people stop using a product that works. |
| COST PER APPLICATION | 10% | Price divided by realistic applications per unit at the label dose — not price per millilitre. |

Total weight: 100%. Where a criterion cannot be assessed from published information it is scored `null` rather than guessed at, its weight leaves the denominator, and the review states the coverage that survived.

## Panel protocol

- **PANEL SIZE:** 12–20 TESTERS PER PRODUCT
- **AGE BAND:** 30–58
- **TRIAL WINDOW:** 8 WEEKS MINIMUM
- **WASH-OUT:** 14 DAYS BEFORE FIRST APPLICATION
- **CONTROL ARM:** VEHICLE-ONLY WHERE THE BRAND SUPPLIES ONE
- **INSTRUMENTED:** CORNEOMETRY · TEWL · ERYTHEMA INDEX
- **SUBJECTIVE:** WEEKLY STRUCTURED PANEL SCORING
- **BLINDING:** TESTERS BLIND TO BRAND WHERE DECANTING ALLOWS
- **ACQUISITION:** PURCHASED AT RETAIL — SEE DISCLOSURE
- **RE-TEST:** ON REFORMULATION OR EVERY 24 MONTHS

Of the 56 products in the register, 0 are panel tested and 56 are desk reviews against published documents. Every review states which it is.

## Disqualifiers

- **UNDISCLOSED CONCENTRATIONS** — If the percentage is not published, the claim cannot be assessed. Disclosure is marked down hard and every efficacy claim resting on the missing number is discounted.
- **JAR PACKAGING FOR OXIDISERS** — Retinoids and ascorbic acid in an open jar degrade before the trial window closes.
- **pH OUTSIDE THE ACTIVE'S WINDOW** — A 20% vitamin C at pH 4.2 is not a 20% vitamin C. Formulation integrity fails outright.
- **“CLINICALLY PROVEN” WITHOUT A METHOD** — No n, no duration, no design, no score. We ask once and publish the answer or the silence.
- **BEFORE / AFTER PHOTOGRAPHY AS EVIDENCE** — Lighting is a more powerful active than anything on the market. It is never accepted as data.
- **PAID PLACEMENT** — No product enters the register in exchange for payment. See the disclosure document.

## Marked down for

- **AN UNPUBLISHED CONCENTRATION** — A formula you cannot read is a formula we cannot assess. It is the single commonest failure in this register.
- **NO CONTAINER SIZE** — Without a fill weight or volume, cost per application cannot be computed and a supply claim cannot be checked.
- **A DAY-30 SATISFACTION FIGURE** — Uncontrolled, unblinded, self-assessed by paying customers. It measures how buyers feel, not what a drug did.
- **“CLINICALLY PROVEN”** — Undefined phrase. We ask proven in whom, at what strength, against what comparator, for how long.
- **A COURSE SOLD AS A SUBSCRIPTION** — Hydroquinone, topical steroids and antibiotics all require a stop. A subscription's default behaviour is to continue.
- **A WARNING ON THE WRONG PAGE** — A contra-indication in a help-centre article is not a warning if nobody is sent to it before paying.
- **“UP TO” FIGURES** — A ceiling is not a result. Every figure here carries its sample size and its comparator arm.
- **BEFORE / AFTER PHOTOS** — Lighting is a more powerful active than anything in this register.

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## Elsewhere in the register

- [Review register](/reviews)
- [Active monographs](/actives)
- [Brand register](/brands)
- [Evidence register](/evidence)
- [The ledger](/ledger)
- [Agent guide](/llms.txt)
- [Sitemap](/sitemap.xml)

_EVERY FIGURE RESOLVES TO A RECORD. NO NUMBER ON THIS SITE IS AUTHORED BY US._