Why we grade evidence
Every ingredient, medication, and procedure on Dermapedia carries an evidence grade. We add it because "there's a study" is not the same as "it works." Our job is to tell you how sure the science is — not just that some research exists.
Our three grades
High — Backed by strong, consistent evidence: multiple randomized controlled trials, or a systematic review that pools them. You can rely on it.
Moderate — Backed by real but limited evidence: smaller trials, mixed results, or industry-funded studies that haven't been widely repeated. Promising, not settled.
Low — Early or weak evidence: lab studies, tiny trials, or mostly theory. It may pan out, but the proof isn't there yet.
What we weigh
- Study type — an RCT counts for more than a consumer survey (see our guide, How to Read a Skincare Study).
- Size — a trial of 500 people tells us more than one of 20.
- Control group — was the treatment compared to a placebo or an alternative?
- Independence — brand-funded studies are counted, but weighted more cautiously.
- Consistency — do several studies agree, or just one?
How we handle brand-funded research
We don't ignore it — a lot of good dermatology research is funded by the companies that make the products. But we note it, and we lean harder on studies that were independent or have been repeated by others.
Our review process
Content is written in plain English, then checked against the primary literature by a board-certified dermatologist before it publishes. Each page shows who reviewed it and when. We update entries as new evidence comes in.
Our promise
Dermapedia carries no ads and no sponsored picks. Nobody pays to be recommended here. When we say something works, it's because the evidence says so — and when the evidence is thin, we tell you that too.
This page is educational and not medical advice.