Good health information starts with good sources. This page explains where our information comes from, how we decide which evidence to trust, and how we cite it.
How we rank evidence
| Level | Type of source | Examples |
|---|---|---|
| 1. First choice | Current clinical guidelines and official health agencies | World Health Organization, CDC, NIH, NICE guidance, ICMR, and guidelines from specialty societies such as the AHA, ADA, ACOG and ASCO |
| 2. | Systematic reviews and meta-analyses | Cochrane Library, and systematic reviews in peer-reviewed journals |
| 3. | Peer-reviewed studies | Research indexed in PubMed, in journals such as The Lancet, NEJM, JAMA and The BMJ |
| 4. | Official medicine labels and patient references | DailyMed drug labels, FDA, MedlinePlus, National Cancer Institute, NHS |
When sources disagree, we follow the most recent high-level guideline and explain the difference where it matters to readers, for example when US and UK guidance differ.
What we do not use as evidence
- Blogs, forums and social media posts
- Other health websites that do not cite primary sources
- Press releases or news reports on their own, without the underlying study
- Product marketing or manufacturer claims, other than official drug labels
- Text generated by AI tools. AI never chooses or creates our sources.
How we cite
- We link to the specific guideline, study or label page, not just a website’s homepage.
- An editor checks every number and range against its source before publication. If we cannot verify a figure, we remove it or describe it in general terms.
- We note when a figure applies only to a certain group, for example adults, or a specific country’s guideline.
- Reference ranges vary between laboratories, so we remind readers to use the range printed on their own report.
Methods behind our health tools
Our tools use published, named methods. Each tool page explains its method and limits. Examples include:
| Tool | Method |
|---|---|
| BMI Calculator | WHO body mass index categories for adults, with the lower WHO cut-off points for Asian populations shown alongside (WHO expert consultation, 2004) |
| BMR Calculator | Mifflin–St Jeor equation (Mifflin et al., 1990) |
| Depression Screening Test | PHQ-9 questionnaire (Kroenke et al., 2001) |
| Mental Well-being Test | WHO-5 Well-Being Index (World Health Organization, 1998) |
| Blood Pressure Tracker | Blood pressure categories from the 2025 AHA/ACC high blood pressure guideline (Jones et al., 2025) |
See all tools on our health tools page.
Found a problem with a source?
If a link is broken, a source is out of date, or you think we have misread a study, email support@mymedicineadvisor.com. Our Corrections and Updates Policy explains what happens next, and our Editorial Policy describes how sources are checked.
Found this helpful? See more of our guides on Google.
Want to see our guides first on Google?
Found this helpful? See more of our guides on Google.