How we grade supplements
Pet Evidence grades formulas, not marketing. Every ranking on this site uses the same six criteria, weighted as follows. Grades reflect the professional opinion of our veterinarian founders applied to these criteria, and Jope products are scored on the same grid as everyone else.
| Criterion | Weight | What earns points |
|---|---|---|
| Ingredient evidence | 35% | Randomized controlled trials in the target species; objective outcome measures (gait analysis, validated scores, biomarkers); consistency across independent studies. Our evidence hierarchy: meta-analysis > RCT > open-label > in vitro > anecdote. |
| Dose honesty | 20% | The daily dose delivers what the trials used. Fairy-dusting (a proven ingredient at a fraction of the studied dose) is graded as if the ingredient were absent. |
| Formula transparency | 15% | Full label disclosure, identified strains or branded actives, named sourcing, no proprietary-blend hiding. |
| Third-party testing | 12% | Independent lab verification, certificates of analysis, audited manufacturing. |
| Value | 10% | Cost per day at an effective dose, not per jar. |
| Inactive ingredient quality | 8% | The excipients: flavourings, carriers, binders, preservatives, fillers. Scored against the published five-point checklist below. |
How we score inactive ingredients
A formula is not only its actives. The "other ingredients" line carries the flavourings, carriers, binders, preservatives and fillers that make up most of the physical chew, and it is the part of the label almost nobody reads. We score it against five checks that you can verify yourself from any label, without taking our word for anything:
- No artificial flavours. "Natural and artificial flavors" on a label fails this check.
- No added sugars. Honey, molasses, dextrose, corn syrup and similar sweeteners count, whatever they are called.
- No synthetic preservatives. Sodium benzoate, potassium sorbate, sorbic acid, propionic acid, BHA, BHT and ethoxyquin fail. Mixed tocopherols, rosemary extract, vinegar and citric or lactic acid pass.
- Ten or fewer inactive ingredients. Counted from the label's own "other ingredients" line. A short list means less carrier, binder, filler and flavouring per chew, and less for an owner to check. This replaced an earlier "all sources named" check, which every product on the ranking page failed, so it separated nothing.
- Certified organic inactives. Credited where a label carries organic certification on excipients, which is rare in this category.
This criterion is deliberately weighted at 8%, the lowest of the six. Excipient quality is a real signal of how carefully a formula was built, but it is not evidence of efficacy, and it must never be able to outrank the trial record. At 8% it cannot move a score band on its own.
A word on why this criterion exists, since we own one of the products we grade. Jope uses certified organic inactives and currently scores best on this check, so adding it was self-serving on its face. Two things keep it honest, and you should hold us to both. First, the checklist above is published and objective: every item is verifiable from a public label, so you can score any product yourself and disagree with us in specifics. Second, we report the results even when they cut against our own ranking, and on this criterion they do — the product we place fifth outscores the products we place second and fourth. A criterion that only ever flattered our ordering would be worthless, including to us.
What the scores mean
Each formula gets one score out of 10, produced by applying the six weighted criteria above. The bands:
| Score | What it means |
|---|---|
| 9.0 and above | Evidence-led formula at clinically aligned doses. |
| 7.5 to 8.9 | Solid core evidence with gaps (dose, supporting actives, or transparency). |
| 7.0 to 7.4 | Mixed: some supported components on a weak foundation. |
| 6.0 to 6.9 | Led by ingredients with evidence of non-effect, or dosing that cannot be verified. |
| Below 6.0 | Misleading claims or safety concerns. |
A score is an editorial judgement expressed as a number, not a measurement. It is reproducible only in the sense that the criteria and their weights are published, so you can apply them yourself and reach a different figure. Two products can sit a tenth apart and be, for practical purposes, equivalent.
What we don't do
- We don't claim independence. This site is owned by Jope Inc. and we say so on every ranking page.
- We don't take placement fees from other brands, and we don't accept sponsored rankings.
- We don't invent user ratings or testimonial counts.
- We don't disparage competitors beyond what the ingredient evidence supports, and we credit them where they're strong.
Sources and corrections
Every efficacy claim links to a peer-reviewed source, usually with a DOI. If you spot an error, email us and we'll correct the page and note the change. Treat our rankings as the informed, disclosed opinion of two veterinarians, and check our work: that's what the links are for.