Sources & citations
A grade is only as good as the evidence under it. Every claim in a review traces back to a named source, and every source is weighted by what kind of study it is. Here is how that works.
What counts as evidence, in order
Not all citations are equal. A claim supported only by cell-culture work cannot earn the same grade as one backed by replicated human trials.
A grade of A requires multiple consistent results at level 1. A B typically rests on levels 1 to 3 with limits noted. Anything sitting only at levels 4 to 5 cannot exceed C. The full rubric lives in the methodology.
Each in-text marker gives author, year, and journal, and points to the primary paper rather than a press release or a secondary summary. Where a study is small, preliminary, or industry-funded, we say so in the same breath as the citation.
Selected references
A sample of the primary literature behind the current reviews. The full list is cited in place on each page.
- Lin WH, et al. Fibroblast growth factors in the hair follicle cycle. Exp Dermatol. 2015.
- Rosenquist TA, Martin GR. FGF signalling in the hair growth cycle. Dev Dyn. 1996.
- Zhang H, et al. Growth factors in hair follicle regeneration. J Dermatol Sci. 2020.
- Olsen EA, et al. Topical minoxidil in androgenetic alopecia: dose-response. J Am Acad Dermatol. 2002.
- Kaufman KD, et al. Finasteride in men with androgenetic alopecia. J Am Acad Dermatol. 1998.
- Lucky AW, et al. Topical minoxidil 5% and 2% in women. J Am Acad Dermatol. 2004.
- Prausnitz MR, Langer R. Transdermal drug delivery. Nat Biotechnol. 2008.
- Barani H, et al. Lipid-based nanocarriers for dermal delivery. Int J Pharm. 2018.
- Nikiforidis CV. Structure and functions of oleosomes. Adv Colloid Interface Sci. 2019.
Where a paper has a DOI or a PubMed identifier, it is included so you can read the original yourself. Found a citation you think is misread or out of date? Tell the editors and we will re-check it.
