Research Methodology
How we find studies, weigh them, and decide what an article can and can't say.
Last updated: November 3, 2026
1. Finding the research
For each topic we search biomedical databases, mainly PubMed, for primary studies and reviews, and we check ClinicalTrials.gov for registered human trials. For regulatory status we go directly to the relevant agency, such as the FDA, WHO, or World Anti-Doping Agency, and note the date we checked.
2. Weighing different kinds of evidence
Not all studies are equal. Broadly, from least to most informative for decisions about people:
| Study type | What it can tell us | Key limitation |
|---|---|---|
| Laboratory (cell) studies | Possible biological mechanisms | Cells in a dish don't behave like a whole person |
| Animal studies | Effects in a living organism; early safety signals | Many results don't carry over to humans |
| Case reports and case series | Early signals in people | No comparison group; prone to bias |
| Observational studies | Associations in real-world populations | Can't establish cause and effect on their own |
| Randomized controlled trials | Whether an intervention causes an effect | Quality depends on size, design, and duration |
| Systematic reviews and meta-analyses | The overall picture across studies | Only as good as the studies they include |
3. Evidence levels used in our articles
Each article carries a short evidence label summarizing the strongest relevant evidence for its main claims:
- Preclinical: evidence comes mainly from laboratory and animal studies. Human benefit and safety are not established.
- Limited clinical: some human data exist, but studies are small, uncontrolled, short, or few in number.
- Moderate: several controlled human studies point in the same direction, with some limitations.
- Established: consistent results from well-designed human trials, often reflected in regulatory approvals or clinical guidelines.
Where an article covers both established and experimental approaches, its label reflects that mix.
4. Things we always check
- Who was studied (cells, animals, healthy volunteers, patients) and how many
- Whether there was a control group and whether participants were randomized and blinded
- Whether results have been independently replicated
- Who funded the research and whether authors have relevant financial interests
- Adverse effects, long-term safety data, and product-quality concerns
- Current regulatory status
5. Citations
References are listed at the end of each article with links to PubMed, a DOI, or the issuing organization. Each reference is checked against its source before publication. If a link breaks or a study is retracted, pleaselet us know.