Lesson 264 of 1455
The Publication Date Check
AI gives you confident answers about facts that may have changed. The publication date of any source is the first thing to check — including AI's training cutoff.
Builders · Research & Analysis · ~9 min read
A 2018 fact in a 2026 paper
If you're researching social media use among teens, a 2018 study isn't useless — but it's missing TikTok's growth, a pandemic, and 8 years of platform changes. Old facts about fast-changing fields can mislead you.
The same applies to AI answers. Most chatbots have a training cutoff — usually 6-18 months before today. Anything that happened after the cutoff is invisible to the model.
When old sources are still good
- Math, physics, geology — slow-changing fields where 1990s papers are still cited
- Historical analysis of fixed events
- Foundational theories (e.g. supply and demand)
When old sources are dangerous
- Technology — anything tech-related more than 3 years old is suspect
- Politics — names, laws, and policies change constantly
- Health guidelines — vaccines, medications, screening recommendations update yearly
- Statistics — population, prices, market share all drift
Key terms in this lesson
The big idea: every source has a date. That date tells you how much time has passed for the world to change since. Always check it.
End-of-lesson quiz
Check what stuck
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Lesson help
Questions are best handled with a grown-up here.
For this age range, Tendril keeps freeform AI chat paused until parent/guardian consent and child-safe moderation are fully verified. Use the quiz, notes, and related lessons below, or ask a parent, guardian, teacher, or librarian to work through the question with you.
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