It can be very challenging to assess what information to believe. One simple way to evaluate evidence is via something called "Hill's Criteria", 9️⃣ considerations to help assess whether an observation has a *causal* component

I'll describe them using xkcd comics 🎉

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Sir Austin Bradford Hill, a statistician & epidemiologist, created a list of guidelines for evaluating whether there is evidence of a causal relationship. He determined the following aspects ought to be considered when assessing causality

https://www.ncbi.nlm.nih.gov/pmc/articles/PMC1898525/pdf/procrsmed00196-0010.pdf

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1️⃣ Strength 💪

👉How big is the effect you are seeing?
👉Note: Hill suggests that huge effects can suggest causality, however this does not mean small effects cannot

https://xkcd.com/539/ 

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2️⃣ Consistency

👉This is essentially reproducibility & replicability
👉Can your analysis be reproduced?
👉Has anyone been able to replicate your findings?

http://xkcd.com/242/ 
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3️⃣ Specificity

👉 Can the association be pinpointed to a specific cause with no other plausible explanation?

http://xkcd.com/1217/ 

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4️⃣ Temporality ⏰

👉Does the timeline make sense?
👉In general, the exposure ought to come before the outcome it is said to cause.

http://xkcd.com/925/ 
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5️⃣ Biological gradient

👉The wording of this point makes it a bit difficult to untangle from the medical application, but generally this refers to a dose effect
👉Does increasing an exposure yield a change in the outcome.

http://xkcd.com/323/ 
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6️⃣ Plausibility

👉Does the causal relationship make sense?
👉This is also a tricky one since plausibility depends on knowledge at the time. If we found it perfectly plausible, we may not need statistics to show the relationship.

http://xkcd.com/605/ 
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7️⃣ Coherence

👉Similar to plausibility, is there a logical argument that can be made by/to experts in the field regarding causality.
👉Does it fit into the understanding of the field

http://xkcd.com/1170/ 
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8️⃣ Experiment 👩‍🔬

👉 If a controlled experiment can take place, this can strengthen the argument for causality
👉 I view this as a general attempt to implement a counterfactual analysis.

http://xkcd.com/1462/ 
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9️⃣ Analogy 👥

👉 Have we seen a similar effect from a similar exposure?

http://xkcd.com/882/ 
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There is lots of incoming information and data these days, hopefully these principles can help a bit with sifting through the noise! I have a blogpost version of this here if that is your 🍵 cup of tea:

https://livefreeordichotomize.com/2016/12/15/hill-for-the-data-scientist-an-xkcd-story/

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