How we grade evidence
The beauty and aesthetics industry spends billions convincing you that everything works. Published research tells a more useful story: some things work well, some work a little, and some have never been properly tested on humans. Our job is to sort which is which and show our sources.
The four grades
Multiple randomized controlled trials or a meta-analysis support this use. The effect is real and repeatable.
Randomized trials support this use, but they are few, small, or short. The effect is probably real. The size of it is less certain.
Only small, short, or lower-quality studies exist. Treat marketing claims about this use with caution.
The marketing has moved faster than the research. There is no good human data behind this use yet.
What we read
Grades come from human clinical research indexed on PubMed, weighted by study design. A meta-analysis of randomized trials outweighs a single trial. A single trial outweighs a case series. A case series outweighs a manufacturer's white paper, which we treat as marketing. Lab and animal studies can explain how something might work, and they never earn a grade on their own. Every page cites the specific papers behind its grades so you can read them yourself.
What a grade does not mean
Strong evidence means the average measured effect is real. It does not promise you the before-and-after photo from an ad, which is usually the best responder under the best lighting. Where studies report numbers, we quote them, because a real 30 percent improvement and a marketing photo are different promises. Results also depend on the person holding the device or needle. A graded treatment done poorly is still a bad treatment.
How we handle money
Proof & Glow takes no advertising, no sponsorships, and no affiliate commissions from any brand, device maker, or clinic. Nothing on this site is for sale. Proof & Glow shares owners with Vera Compare, a med spa price comparison site, and links there from treatment pages are always labeled. Spas cannot pay either site to change a grade, a ranking, or a word of an entry.
Corrections
Research moves and grades should move with it. When new trials change a grade, we update the page and note what changed. If you think we got something wrong, write to [email protected] with the study and we will read it.