Our Evidence Grading System
How we evaluate and rate the scientific evidence behind hair loss treatments and procedures.
Evidence-Based Medicine
We use the same evidence grading principles used by major medical organizations to help you distinguish between proven treatments and unsubstantiated claims. Every treatment on our site is assigned a grade based on the quality and consistency of scientific research.
Grading Scale
Grade A — Strong Evidence
Multiple high-quality randomized controlled trials (RCTs) with consistent results. FDA-approved for this use. Strong recommendation for use.
Based on:
- • Multiple well-designed RCTs with large sample sizes
- • Systematic reviews and meta-analyses
- • Consistent results across studies
- • FDA approval or international equivalent
Examples: Minoxidil, Finasteride, Hair Transplant Surgery
Grade B — Moderate Evidence
Some RCTs or consistent observational studies. Generally positive results but limitations in research quality or quantity. Reasonable option to consider.
Based on:
- • Limited RCTs with smaller sample sizes
- • Well-conducted observational studies
- • Some inconsistency across studies
- • May be FDA-cleared but not approved, or used off-label
Examples: Dutasteride (off-label), Low-Level Laser Therapy, Microneedling
Grade C — Limited Evidence
Small studies, case reports, or conflicting results. Promising but needs more research. Consider with caution.
Based on:
- • Small pilot studies
- • Conflicting or inconsistent results
- • Case series or expert opinion
- • Theoretical rationale but limited clinical data
Examples: PRP Therapy, Topical Finasteride, Some Nutritional Supplements
Grade D — Weak or No Evidence
No reliable studies, negative results, or only anecdotal reports. Not recommended based on current evidence.
Based on:
- • No quality studies or consistently negative results
- • Anecdotal evidence only
- • Theoretical claims not backed by research
- • Studies with serious methodological flaws
Examples: Most "Miracle" Supplements, Essential Oils, Growth Shampoos
Grade W — Wellness/General Health
General health practices that may support hair health but aren't treatments for hair loss. Part of overall wellness.
Includes:
- • Balanced nutrition and diet
- • Stress management
- • Adequate sleep
- • Gentle hair care practices
Examples: Healthy Diet, Stress Reduction, Proper Hair Care Routine
Our Review Process
1. Literature Review
We search peer-reviewed medical journals, clinical trial databases, and systematic reviews for the latest research.
2. Expert Consultation
Board-certified dermatologists and hair restoration surgeons review our assessments for accuracy.
3. Regular Updates
We monitor new research and update grades as evidence evolves. Each article shows last review date.
Key Sources We Reference
PubMed / MEDLINE
U.S. National Library of Medicine database
Cochrane Library
Systematic reviews of healthcare interventions
FDA Drug Database
Official drug approvals and safety information
Clinical Guidelines
American Academy of Dermatology, ISHRS, and other professional societies
Important Note
Evidence grades help you understand research support for treatments, but they don't replace personalized medical advice. What works best for you depends on your specific condition, health status, and preferences. Always consult a qualified healthcare provider before starting treatment.