Methodology
How Firsthand Ranks and Reviews Products
Firsthand's methodology in brief
Firsthand scores every health product and service on five published, fixed-weight criteria: Safety (30%), Evidence Quality (30%), Cost & Value (20%), Transparency (10%), and Customer Support & Experience (10%). Safety scoring draws on ingredient and provider safety profiles plus FDA warnings; evidence scoring rests on peer-reviewed clinical research, with randomized controlled trials weighted highest. Firsthand reviews products it earns no commission from as well as products it does; rankings are never sold, and affiliate partnerships never change a score. Every money page lists cons and red flags alongside benefits, is medically reviewed before publication, and carries a visible last-updated date. The same rubric applies to every product in a category, so scores are directly comparable — a product can rank first while Firsthand earns nothing from it. The full rubric below explains each criterion in detail, including how manufacturer-funded studies and regulatory warnings are handled.
Most review sites keep their scoring rules vague, which makes it impossible to tell an honest recommendation from a paid one. We take the opposite approach: the exact criteria and weights behind every Firsthand ranking are published on this page, and they apply to every product in a category — whether or not we have any financial relationship with its maker.
The five scoring criteria
| Criterion | Weight | What we evaluate |
|---|---|---|
| Safety | 30% | Ingredient and provider safety profile, known interactions and contraindications, FDA warning letters and safety communications, and manufacturing standards. |
| Evidence Quality | 30% | Peer-reviewed clinical research behind the product's core claims. Randomized controlled trials are weighted highest, then systematic reviews, then observational studies. Marketing claims without published evidence score zero here. |
| Cost & Value | 20% | Price per effective dose or per month of service, compared against alternatives that deliver the same evidence-backed benefit. Hidden fees, forced subscriptions, and cancellation friction lower this score. |
| Transparency | 10% | Label accuracy, full ingredient disclosure (no proprietary blends hiding doses), third-party testing, and honest marketing that doesn't overstate the science. |
| Customer Support & Experience | 10% | Responsiveness, refund and return policies, shipping reliability, and the real-world experience reported by verified customers. |
How we weigh the evidence
Evidence Quality is scored from the primary literature, not press releases. We search PubMed and NIH trial registries for studies on the product's actual formulation or service model. Randomized controlled trials count most; systematic reviews and meta-analyses of those trials strengthen a score further. Small pilot studies, animal research, and in-vitro results are noted but weighted lightly. A study funded by the manufacturer isn't disqualified, but we say so, and we look for independent replication.
Safety scoring starts with the same literature and adds regulatory signals: FDA warning letters, recalls, adverse-event reports, and — for telehealth providers — the clinical oversight built into their prescribing process.
Independence: how money never touches the scores
- We review products we don't earn from. Category rankings include products and providers that pay us nothing. If the best product in a category has no affiliate program, it still ranks where the rubric puts it.
- Rankings are never sold. No company can pay for a position, a score, or a favorable sentence. There are no "sponsored" slots inside our rankings.
- Affiliate partnerships never change scores. Scoring is completed against the rubric before monetization is considered. Whether a link earns a commission has no input into any criterion. Read our full affiliate disclosure.
- Every money page lists cons and red flags. If we recommend a product, we also tell you who it's wrong for, what the side effects are, and where the evidence is thin.
- Every money page is editorially fact-checked. Our editorial team checks health claims against their cited sources before a monetized health page is published. See our editorial policy.
- Pages carry last-updated dates. Evidence changes. Each ranking and review displays when it was last updated, and we re-check pages when new trials, recalls, or pricing changes warrant it.
What a score means
Each criterion is scored 0–10 against the rubric above, multiplied by its weight, and summed into a final score out of 10. Products in the same category are scored against the same rubric on the same day, so scores are directly comparable within a ranking. A high score is not a medical endorsement — it means the product performed well on safety, evidence, value, transparency, and support relative to its competitors. Talk to your clinician before acting on any ranking.