Who writes this, how the grading works, and what it cannot tell you

Who writes this

Latherlogic is written by people who read studies carefully and have no medical training. That is the whole disclosure. There is no doctor on this masthead, no dermatologist checking the copy and no clinical advisory board, and no page here claims any kind of medical review, because the claim would not be true.

What we can do is read a paper properly and report it without decoration: the number of participants, the length, the comparison group, the outcome measured, and the funder. What we cannot do is tell you what is happening to your hair or what to do about it. Those are jobs for a GP or a board-certified dermatologist, and no amount of reading substitutes for one.

The scale, in full

Every active is scored on four questions. The weights are published so you can disagree with them, and the sub-scores are printed on the money page so you can see which part of a grade is carrying it.

1. Trials in hair loss, four points. Nothing found scores zero. An uncontrolled study, or one compared only against another active with no untreated group, scores one. One placebo- or untreated-controlled trial scores two. More than one scores three. More than one, independent of the seller and agreeing, scores four.
2. Who paid, two points. The seller or the ingredient's maker scores zero; unstated or mixed scores one; independent of the seller scores two.
3. What was counted, two points. Self-report or photographs score zero; an investigator's rating or a hair-pull test scores one; hairs counted or measured score two.
4. Shelf product versus trial, two points. Different strength, different form or different condition scores zero; a partial match scores one; the same product used the same way scores two.

Eight to ten is as good as this aisle gets, five to seven is mixed with real caveats, three to four is thin, and nought to two means nothing published that we could find. Nothing on this site currently reaches eight.

Why an ingredient sometimes gets no grade

If we have not read a trial at the source, we do not score it. Two actives on this site are published with no grade for exactly that reason, and their rows say so. The alternative — taking a number from a review's summary table and presenting it as ours — would look identical on the page and mean nothing at all.

This cuts in awkward directions on purpose. One of the ungraded actives is the house ingredient of a company we link to. It stays ungraded.

What this site will not publish

• Before-and-after photographs, ours or anyone else's. A haircut and a ring light move one further than any ingredient here.
• Dosing. How much, how often and for how long belong to the product's own label and to a prescriber, and we will not restate them as advice.
• Percentages we did not read in a source, or ranges invented to sound careful.
• Testimonials, user ratings, or any sentence implying we tried a product. Nothing on this site has been tested by us; every grade is a reading of somebody else's work.
• Prescription-only treatments as recommendations. Where one is relevant we name what it is and send you to a prescriber.
• Clinic or brand rankings of any kind.

How the sources are kept

Every fragile fact on this site — a trial, a participant count, a regulator's decision, a label's wording, a price on a seller's own page — is recorded with its source and the date we read it. The dates matter: labels change, storefronts change currency by region, and a 2003 trial is still a 2003 trial. Where a source contradicts itself or another source, we print neither number rather than choosing the more interesting one.

If something here is wrong, the correction is welcome and the page gets changed. Contact has the address, and who pays us has the commercial side in full.