| Dimension | Scoring Notes | Score |
|---|---|---|
| Study Design | Multiple high-quality human RCTs for skin hydration, elasticity, and wrinkle reduction. Also strong RCT evidence for joint pain and bone density. Among the best-evidenced cosmeceutical/supplement compounds in catalog. |
25 / 25 |
| Sample Size | Well-powered trials: VERISOL studies 60-100+ participants; joint studies up to 200+. Cumulative sample substantial for the field. |
20 / 20 |
| Replication | Replicated across multiple independent research groups in Germany, Japan, US, and Brazil. Both hydrolyzed collagen peptide effects and joint cartilage effects independently replicated. |
20 / 20 |
| Journal Impact Factor | Published in Skin Pharmacology and Physiology (IF ~3), Nutrients (IF ~4), Journal of the International Society of Sports Nutrition (IF ~4). Respectable journals for the field. |
8 / 15 |
| Funding Independence | Significant GELITA and Rousselot (collagen manufacturers) funding. Pre-registered trials but industry dominates. Some independent academic work from sports nutrition groups. |
4 / 10 |
| Population Diversity | Studies span women (skin trials), athletes (joint trials), and elderly populations. More diverse than most supplement evidence bases. |
3 / 5 |
| Researcher h-Index | Key researchers include Steffen Oesser (GELITA-affiliated, h-Index ~20+) and independent sports nutrition investigators. Mixed — some industry affiliation. |
2 / 5 |