Methodology and sources
How we work
- Start from an entry in the open-licensed HowToLiveBetter project.
- Find the primary source for each claim: official agencies (CDC, NHTSA, WHO, USPSTF), systematic reviews (Cochrane) and major journals (JAMA, Lancet, NEJM).
- Keep only claims we can back with a source we can link. If a number cannot be tied to a stable source, we drop it or state it without the number.
- Rewrite in plain English and note where rules differ by country.
- Tools such as AI assistants may help with translation and drafting; people check the sources and the final text.
Evidence grades
| Grade | Meaning |
|---|---|
| A | Randomized trials, systematic reviews, or official surveillance and estimates |
| B | Observational studies and surveillance with strong expert consensus |
| C | Limited or mixed evidence; treat as a reasonable default only |
Sources we use
Limits
Official schedules (vaccines, screening) change. Check the current official page before acting. Spotted an error? Tell us and we will fix it.
Attribution
Adapted from HowToLiveBetter by eternity4719, CC BY 4.0. Changes were made.