Safety-assessed
The baseline every market requires before launch.
- Safety assessment report
- Stability & challenge test
- Microbial limits & heavy metals
“Safety-assessed for cosmetic use”
Service · Claims support
The right evidence for every claim on your pack.
CSL claims scientists map each claim you want to make to the evidence it needs, then set up and coordinate the patch tests, use trials and efficacy studies, as one step in your product's development.
Guires Cosmetic Science Lab
Cosmetic Claims Testing from Guires CSL
Cosmetic claims testing and support for cosmetic clinical trials: patch test, HRIPT, in-use and instrumental efficacy studies with Corneometer, TEWL and Cutometer, designed so every claim meets the common criteria of Reg 655/2013 and the rules in your other markets. Each study is planned for claims substantiation from the start and run to Good Clinical Practice, with ethics committee approval where the study design requires it.
Start your project with Guires CSLWhat's included
The work, in detail.
Claim mapping
Your pack and marketing claims listed, graded and matched to the evidence each market expects.
Skin safety studies
Single-application patch tests and HRIPT for "dermatologically tested" and "hypoallergenic" claims.
In-use safety
Dermatologist-assessed use over two to four weeks, including sensitive-skin panels.
Instrumental efficacy
Hydration, barrier, firmness, wrinkles, tone and oil control measured with skin instruments.
Consumer perception
Self-assessed claims such as "9 in 10 agree", from structured consumer panels.
Claims support · evidence tiers
Match the evidence to the promise.
Not every product needs a 12-week clinical. We scope the study to the claim you want to make, so you pay for the proof you need and nothing more.
Dermatologically tested
Human safety data for claims that name a test or a skin type.
- Everything in Tier 1
- 48 h patch test or HRIPT
- Dermatologist-assessed in-use study
“Dermatologically tested · Hypoallergenic”
Clinically proven
Instrumental efficacy studies behind numbers and timelines on pack.
- Everything in Tier 2
- Instrumental efficacy endpoints
- Statistics and claim wording review
“Clinically shown to reduce fine lines in 28 days”
Claim-to-test finder
Tell us the claim. We'll map the proof.
Pick what you want printed on the pack. We'll show you the typical study plan behind it.
Your claim
Typical study plan
Dermatologically tested
“Dermatologically tested. Suitable for all skin types.”
- Safety assessmentIngredient-by-ingredient review at use level
- Single-application patch test48 h occlusive, dermatologist-graded
- In-use safety study2–4 weeks, including a sensitive-skin sub-panel
Typical study plan
Hypoallergenic
“Hypoallergenic. Formulated to minimise allergy risk.”
- Allergen screen of formulaEU fragrance allergen list + sensitiser review
- In-vitro sensitisationOECD 442C/D/E on any new active
- HRIPTInduction and challenge on 100+ volunteers
Typical study plan
SPF 50 · PA++++
“Broad spectrum SPF 50, PA++++.”
- Photostability & stabilityAccelerated storage under UV exposure
- In-vivo SPFISO 24444 on a qualified human panel
- UVA protectionISO 24443 in-vitro, ISO 24442 for PA rating
Typical study plan
24-hour hydration
“Clinically shown to hydrate skin for 24 hours.”
- Baseline measurementCorneometer on conditioned volunteers
- Single-application kineticsReadings at 1, 8 and 24 hours vs untreated site
- Statistics & reportSignificance testing and claim wording review
Typical study plan
Reduces fine lines in 28 days
“Visibly reduces fine lines in 4 weeks.”
- Baseline imaging3D skin topography of the crow's-feet area
- 28-day use studyTwice-daily use with compliance diaries
- Instrumental + expert gradingImaging, Cutometer and dermatologist scoring
Clinical trial support
When a claim needs a trial, we set it up.
Clinical work is one step in your product’s development, not a separate project. We design the study around your final formula and pack claims, coordinate ethics approval, dermatologist-led panels and instrumental readings, and feed the results into your label and dossier.
Hydration mapping · Corneometer| Endpoint | Instrument | Typical claim |
|---|---|---|
| Hydration | Corneometer | “Hydrates for 24 hours” |
| Barrier | TEWL · Tewameter | “Strengthens the skin barrier” |
| Firmness | Cutometer | “Visibly firmer skin” |
| Wrinkles | 3D topography | “Reduces fine lines in 28 days” |
| Tone & spots | Chromameter | “Fades dark spots” |
| Oil control | Sebumeter | “Controls shine for 8 hours” |
| Sun protection | ISO 24444 · 24443 · 24442 | “SPF 50, PA++++” |
Sectors & applications
Claims & clinical for every sector and application
Guires CSL plans claims testing and clinical studies for every sector below, choosing the instruments, panels and endpoints that prove each application, from hydration to hair density.
Sectors
Skin careSerums, moisturisers, cleansers, masksExplore 
Sun careSPF, tinted SPF, after-sunExplore 
Hair & scalp careShampoo, conditioner, serums, oilsExplore 
Colour cosmeticsFace, lip, eye and nailExplore 
Body wash & body careWashes, shower oils, lotions, scrubsExplore +6More sectorsPersonal care & hygiene, Men's grooming, Baby & kids and moreSee all Applications
Anti-ageing & wrinklesFine lines, firmness, elasticityExplore 
Acne & oil controlBlemishes, shine, poresExplore 
Hyperpigmentation & even toneDark spots, uneven toneExplore 
Hydration & barrier repairMoisture, barrier, drynessExplore 
Sensitive skin & rednessCalming, low-irritation formulasExplore +5More applicationsSun protection, Hair fall & hair growth, Dandruff & scalp health and moreSee all Evidence-based
From published evidence to a product that passes regulatory review
Every Guires CSL claims testing and clinical studies project starts from published science and ends with evidence regulators and retailers accept: data from the literature where it exists, and tests, in vitro studies and clinical trials where it does not.
Published evidencePeer-reviewed randomised controlled trials behind the actives we formulate with, linked to PubMed.Explore Standards and regulationsTechnical guides to ISO 11930, the EU CPSR and the terms that decide whether a product can go to market.Explore Proof from projectsCase studies showing how the evidence was built and what clients received.Explore
Deliverables
What you receive.
Claims matrixEvery claim, its evidence tier and the study behind it
Study protocolDesign, panel size, endpoints and ethics documents
Study reportResults with statistics, ready for your product file
Claim wording reviewFinal pack wording checked against the results and each market
Marketing summaryPlain-language results your team can use
How it runs
Step by step.
- Claims workshopList every claim you want and the markets they go to
- Evidence planTier and study chosen for each claim
- Study set-upProtocol, ethics approval, panel recruitment
- Study runDermatologist-led readings and instrument measurements
- Report & wordingResults feed straight into label and dossier
Market insights from Guires CSL scientists
Stay ahead in claims testing and clinical studies with regulation updates, the latest research, ingredient spotlights, recalls and market trends, written by the Guires CSL formulation, testing, clinical and regulatory teams.
Explore market insights
Questions
Asked before we start.
Are you a clinical research organisation?
No. We are a product development partner. Clinical trials are one step we plan and coordinate for your product, alongside formulation, testing and regulatory work.
Can I make a claim without a clinical study?
Often, yes. Many claims can be supported by ingredient data, in-vitro tests or consumer perception studies. The claim finder above shows typical routes.
How many volunteers does a study need?
It depends on the endpoint. Instrumental efficacy studies often start around 20 volunteers; HRIPT panels typically run from 50 to 200.
Related services
Often paired with this.
Guires CSL quality, compliance and safety
Every claims testing and clinical studies project at Guires CSL runs inside an ISO 9001 certified quality system, with documented methods, calibrated instruments, traceable raw materials and reviewed reports, so the results behind your product can be checked and defended.
Guires CSL quality & accreditations
In their words
What clients say.
“Rather than starting from broad marketing claims, we worked back from what could realistically be measured, turning our objectives into defensible clinical endpoints.”
“Participant criteria, assessment methods and outcome measures were aligned precisely with the benefits under investigation, giving our study a rigorous scientific structure.”
“Study findings and proposed claim wording were reviewed side by side, so every statement we publish stays firmly grounded in the available evidence.”
Insights
Related reading.
Guidance from our formulation, testing and regulatory teams on the topics this page covers.
“Dermatologically tested”: what the claim needs behind it
Patch tests, in-use studies and panel sizes, and how wording differs between markets.
Read article
Recall: hand sanitiser pulled from US shelves over hidden methanol
An alcohol-based hand sanitiser made in Mexico was recalled after testing found undeclared methanol. What happened, and the controls that prevent it.
Read article
MoCRA for brands outside the US: what you need before you ship
Facility registration, product listing, US Agent, safety substantiation and adverse event reporting, in the order to tackle them.
Read articleFrom the CSL bioscience lab
Tested at the Guires R&D Innovation Centre.
Start a project
Create your next product with CSL.
Our formulation chemists, testing scientists and regulatory specialists work alongside your team, from the first brief to a market-ready product. Bring a brief, a benchmark or just an idea: a scientist will reply within one working day with next steps and an indicative scope.