Our Science-Led Review Process | Skin Science Review

Proposed standards, not completed testing. Current articles compare published product information. We have not purchased or tested the products, documented customer outcomes or obtained doctor sign-off. Scores will only be used when supported by completed evaluations.

1. Research Phase

Before testing, review peer-reviewed studies on key ingredients, including the concentrations studied, proposed mechanisms and potential side effects. Distinguish laboratory research from human trials and finished-product evidence.

2. Independent Purchase

For an independent hands-on review, purchase products through regular retail channels with our own funds. Do not accept free samples or special arrangements as a substitute for an independent purchase.

3. Extended Testing

The proposed minimum testing period is 4–8 weeks. Anti-aging products may require longer observation. Document the duration and limitations rather than promising a result within a fixed time.

4. Documentation

Use standardized photography with consistent lighting to document changes over time. Record application, other products used and any adverse reactions, without treating photographs as clinical proof.

5. Analysis & Writing

Combine documented observations with relevant research to create clear, comprehensive reviews. Explain drawbacks, uncertainty and relationships that could influence placement.

Our rating system

This is the proposed scale for future completed reviews. Ratings describe a product in its evaluated context and do not guarantee the same results for every reader.

5/5

Exceptional

Strong supporting evidence, documented results and excellent value within a completed review.

4/5

Very Good

Positive documented performance with minor drawbacks or value considerations.

3/5

Average

May suit some readers, with meaningful limitations or stronger alternatives.

2/5

Below Average

Limited documented effectiveness or poor value in the evaluated context.

1/5

Not Recommended

Insufficient benefit or documented concerns that prevent a recommendation.

Disclosures and corrections

Koppa Beauty is our recommended brand in our copper-peptide guides. Our detailed coverage explains its GHK-Cu ingredient approach and supporting formula choices; its first position is requested by the site owner, not an independent performance ranking. Owner-requested recommendation placements are disclosed, and product details are checked against their sources when information changes.

Read our disclosure