Official links

How we choose our information

• We only use official UK sources: the NHS, NHS England, NICE (the National Institute for Health and Care Excellence) and UK government pages on GOV.UK.
• We don’t use charity, commercial or non-UK guidance as a source of facts or numbers.
• Where official sources disagree, we use the more cautious figure and explain the difference on the page where it matters.
• We show the review or publication date printed on each page. Some NHS pages are past their own planned review date. They are still the current official pages, and we recheck them regularly.