Our selection method
We select products for a distinct role in the comparison: ingredient approach, formula transparency, routine preferences, price positioning and purchase availability. A larger affiliate commission, a longer ingredient list or a higher advertised concentration does not earn a higher position.
Our accessible, mid-range and premium labels describe editorial market positioning at the time of research. They are not live price quotes or fixed currency thresholds. Check the merchant’s current one-time total before ordering.
What counts as evidence
Official product pages are the source for identity, ingredients, stated use and manufacturer claims. They do not independently prove efficacy. Research is described at its actual level: an ingredient experiment, animal work, a consumer-perception study or an appropriately measured finished-product trial.
Where details are missing, we explain the uncertainty. We do not manufacture scores, star ratings, aggregate customer sentiment or a clinical winner from unrelated studies. Product reviews are research-based and have not been personally tested.
Dates and corrections
The source-check date is the date we reviewed the cited material. It is not a date of personal product use, a guarantee of current stock or an automatically refreshed claim. Ingredient lists and delivery terms can change by region and over time.
We correct meaningful factual errors and reassess affected comparisons. A source update, reformulation or new study may change a verdict. Contact the publisher with the exact page and a primary source to help us investigate.
Photography
Our salon-style portraits and scalp-care scenes are AI-generated editorial imagery. They illustrate a general hair-care routine; they do not show real clients, product testers, endorsements or treatment results.
Product photographs are sourced from the official brand pages linked below and are shown to identify the products discussed in our independent reviews. Brand photographs and trademarks belong to their respective owners. Packaging can vary by region or change over time. We do not generate imitation product packaging.
Product photography credits
- The Ordinary: Multi-Peptide Serum for Hair Density
- Divi: Scalp Serum
- Neurogan Health: GHK-Cu Hair & Scalp Serum
- RevivSerums: RevivHair Max Hair Stimulating Serum
- TYPEBEA: G1 Overnight Boosting Peptide Serum
- The INKEY List: Caffeine Stimulating Scalp Treatment
- Vegamour: GRO Hair Serum
- Living Proof: Scalp Care Density Serum