How we rate
How we choose sources, assign evidence ratings, check every article and make money.
Every article on Years & Yield follows the same process. You should always be able to check what a claim rests on and how certain it is.
The evidence rating
Each title carries one of three ratings. It applies to the article’s main claim; when the picture is mixed, the lower rating applies.
- Strong evidence: several high-quality studies or reviews reach the same result. For money topics: settled by law or by arithmetic.
- Moderate evidence: good indications, but uncertainty about size, duration or transferability.
- Weak evidence: single studies, animal or mechanism data, forecasts. We then say plainly: “Not yet proven.”
Which sources count
| Rank | Health | Money |
|---|---|---|
| 1 | Systematic reviews and meta-analyses, official guidelines (WHO, medical societies, public health agencies) | Laws and authorities (tax and social security offices, regulators), peer-reviewed finance research |
| 2 | Randomized controlled trials | Long-term market data, fund documents, central banks |
| 3 | Observational and cohort studies | Industry studies, reputable business media |
| 4, context only | Animal studies, mechanisms, expert opinion | Forecasts, opinions, provider marketing |
Every number in the text links to a numbered source at the end of the article.
How an article is made
- Research from primary sources.
- Draft written with the help of AI (Claude).
- Fact check by a separate review step that did not write the draft: every claim against its source, every number recalculated, plus titles, descriptions and image text.
- Check against our red lines.
- Approval by the publisher, who carries editorial responsibility.
After publication we revise articles every 6 to 12 months or when new evidence appears. Corrections are noted in the article.
Our red lines
- No cure claims, diagnoses or medication dosing instructions.
- No personal investment recommendations and no promised returns.
- No invented quotes, experts or studies.
- No recommendations of supplements for diseases.
- No recommendation that exists only because of a commission.
How we make money
Years & Yield is funded by advertising, affiliate links and our own digital products. Ads are always labeled “Advertisement.” With affiliate links we earn a commission if you sign up; this is stated right next to the link and never changes a rating.
Images
Cover images are AI illustrations and labeled as such. Charts are drawn in code from the article’s numbers so they are exact.
Our articles do not replace personal medical, financial or legal advice.
Updated October 16, 2026