Pyramid of Final Formulation Testing
For Cosmetic Skincare
1
Biopsy
Biomarkers
Randomised
Controlled CT
Studies where objective scientific measurement uses skin biopsies and biomarker analysis—ideally performed on human volunteers. Where this is not feasible, skin explants or full-thickness skin equivalents may be used. In all cases, results are compared against a control product, ideally the same formulation without the active components
The Manchester Patch Test Assay is an example of this type of study on a group of volunteers and is considered the gold-standard of testing for cosmetic skincare products.
2
Non-Invasive
Randomised
Controlled CT
A study where objective scientific measurements of surface changes are performed on a group of volunteers who have used the product (with active ingredients) for a period of time, and a comparison is made to a 'control' product (which is ideally the same formulation without the active components).
3
Non-Invasive
Clinical Trials (CT)
A study where objective scientific measurements of surface changes are performed on a panel of volunteers who have used the product for a period of time.
This is the most common trial used when a cosmetic brand notes: "Clinically proven to…"
4
Consumer Studies
A survey of a panel of volunteers who have used the product for a period of time to understand their experience of the product.
This test is useful to ensure a consumer's experience matches more rigorous scientific measures. This is the most common study used in cosmetic testing, which you’ll often see as: "90% of people experienced..."
Understanding the Pyramid of Formulation Testing
Follow our key to help understand exactly what each element of the pyramid means.
Randomisation: Clinical trials use randomised participants (picked at random) in two groups by the trial conductors to ensure these groups remain unbiased.
Controlled: A controlled skincare trial includes comparison treatments to understand what’s driving results. The negative control is typically the vehicle - the product base without active ingredients — used to show the effect of the formulation alone, while a positive control may be included to demonstrate what a known, effective treatment looks like in the same test.
Blinded trial: Blinding refers to where the researchers undertaking the study are not aware of which participants / samples are being tested (product or control). A double blinded trial is a blinded trial where the participants are also unaware which product is being used.
For cosmetic products final formulation testing to prove effect often isn't required and the level of evidence is very different than what is required for drug testing. Most cosmetic products lean on level 3 and 4 of the formulation testing pyramid for testing their final formulation. At The Skin Diary, research and proof is crucial to our ethos, which is why we endeavour to conduct our studies at level 1.