Most claims you will read about peptides trace back to a study. Very few of the people repeating the claim have read it. You do not need training in statistics to tell a strong result from a weak one. You need six questions.
1. Was it in humans?
A great deal of peptide research is in cell cultures or rodents. That work is legitimate and it is how things start, but the translation rate from mouse to human is poor. If a claim rests on animal data, it is a hypothesis, not a finding.
2. How many people, and who were they?
Twelve participants is a pilot. Twelve young male athletes tells you very little about a fifty-year-old woman. Check whether the population resembles you before you assume the result does.
3. Was there a control group?
Without a comparison group you cannot separate the compound from time, expectation, or the fact that people who enrol in studies tend to tidy up their habits. Randomised and placebo-controlled is the standard worth looking for.
4. How long did it run?
Four weeks tells you about four weeks. For anything framed around ageing, recovery over a season, or body composition, short trials are close to meaningless.
5. What did they actually measure?
This is where most headlines break down. A study may measure a blood marker that is associated with an outcome, rather than the outcome itself. Moving a marker is not the same as changing how someone feels, performs or ages. Ask whether the thing measured is the thing you care about.
6. How large was the effect?
Statistically significant means unlikely to be chance. It does not mean large or useful. With enough participants, a trivial difference becomes significant. Look for the size of the change, not just whether it cleared a threshold.
A shortcut
If a claim cannot survive the question which sequence, at what dose, in whom, for how long, measured how, it is marketing. That single sentence will filter out most of what you read online.
Reading the study is the slow way, and it is still the only reliable one. Where a listing on this site describes research, it describes the direction of it rather than promising you an outcome, which you can check for yourself in the store. If the terminology is the obstacle, the plain-language guide is the place to start.