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In this video, we look at how scientists link together a risk factor with a noncommunicable disease. To do this, they use a process called epidemiology. We explore how this works and look at the idea of correlation. We then explore problems with sampling.

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Music credit:

Deliberate Thought by Kevin MacLeod is licensed under a Creative Commons Attribution licence (https://creativecommons.org/licenses/...)
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Image credits:

Cigarette in ashtray By © 2005 by Tomasz Sienicki [user: tsca, mail: tomasz.sienicki at gmail.com] Photograph by Tomasz Sienicki / Own work, CC BYSA 3.0, https://commons.wikimedia.org/w/index...

Lung cancer By Emmanuelm at en.wikipedia, CC BY 3.0, https://commons.wikimedia.org/w/index...

Sausage CC BYSA 3.0, https://commons.wikimedia.org/w/index...