Cognitive BiasesPublic knowledge library

Practice Lab

Checking claims & misinformation

Learn to connect a practical check with the evidence-reviewed lens behind it. A real situation can involve several patterns, so each exercise asks for the best first lens among the listed options, not a diagnosis.

How to use this set

Read the check. Choose a lens. Then inspect the evidence.

Use these evidence-reviewed lenses when deciding whether a repeated claim is trustworthy, checking a correction, or testing an explanation against plausible alternatives.

Read the full decision guide before or after the set.

Exercise 1 of 6

In checking claims & misinformation, which lens does this check belong to: “Am I using the same evidence standard for information that supports and challenges the claim?”

  1. Confirmation Bias
  2. Congruence Bias
  3. Illusory Truth Effect
Show the best first lens

Confirmation Bias

Am I using the same evidence standard for information that supports and challenges the claim?

Evidence note Confirmation bias is an umbrella label for several ways existing beliefs or hypotheses can influence information search and interpretation. It should not be reduced to one behaviour such as reading only agreeable news, and a preference for confirming tests is not irrational in every task or environment.

Read the evidence review · Open the decision guide

Exercise 2 of 6

In checking claims & misinformation, which lens does this check belong to: “Would this test distinguish the preferred explanation from plausible alternatives, or would they predict the same result?”

  1. Illusory Truth Effect
  2. Availability Heuristic
  3. Congruence Bias
Show the best first lens

Congruence Bias

Would this test distinguish the preferred explanation from plausible alternatives, or would they predict the same result?

Evidence note Congruence Bias is a narrower hypothesis-testing pattern than the broad umbrella of confirmation bias. In classic work, people overvalued tests that were likely to return a positive result if their leading hypothesis were true, even when other tests were more diagnostic among competing hypotheses. The useful claim is not that every positive test is irrational: a positive test strategy can be efficient in some environments, and the problem depends on whether the chosen test can actually distinguish the focal hypothesis from alternatives.

Read the evidence review · Open the decision guide

Exercise 3 of 6

In checking claims & misinformation, which lens does this check belong to: “Does this feel true because it was independently verified, or because I have encountered the same claim repeatedly?”

  1. Continued Influence Effect
  2. Illusory Truth Effect
  3. Availability Heuristic
Show the best first lens

Illusory Truth Effect

Does this feel true because it was independently verified, or because I have encountered the same claim repeatedly?

Evidence note Repeated information is, on average, judged as more truthful than comparable new information. The size of the effect varies with the material and procedure, and repetition does not make every claim believable or erase all prior knowledge.

Read the evidence review · Open the decision guide

Exercise 4 of 6

In checking claims & misinformation, which lens does this check belong to: “Is the example easy to recall because it is representative, or because it is vivid, recent, emotional, or repeated?”

  1. Availability Heuristic
  2. Continued Influence Effect
  3. Backfire Effect
Show the best first lens

Availability Heuristic

Is the example easy to recall because it is representative, or because it is vivid, recent, emotional, or repeated?

Evidence note Availability is a judgment heuristic: people can use how easily examples or scenarios come to mind when estimating frequency or probability. That shortcut is not automatically an error because memorable or accessible examples can correlate with real frequency. Bias appears when accessibility is driven by factors that are not diagnostic of the quantity being judged.

Read the evidence review · Open the decision guide

Exercise 5 of 6

In checking claims & misinformation, which lens does this check belong to: “After the correction, am I still using part of the old information when explaining or judging the situation?”

  1. Backfire Effect
  2. Confirmation Bias
  3. Continued Influence Effect
Show the best first lens

Continued Influence Effect

After the correction, am I still using part of the old information when explaining or judging the situation?

Evidence note The continued influence effect describes a specific pattern: false or outdated information can keep affecting later reasoning even after a clear correction. It does not mean the correction had no effect, that the person rejected the correction, or that belief in the false claim became stronger. Corrections often reduce misinformation reliance without removing it completely. That distinction matters because continued influence is much broader than the rarer backfire outcome.

Read the evidence review · Open the decision guide

Exercise 6 of 6

In checking claims & misinformation, which lens does this check belong to: “Did belief in the corrected false claim actually become stronger, or am I calling disagreement or incomplete updating a backfire?”

  1. Congruence Bias
  2. Backfire Effect
  3. Confirmation Bias
Show the best first lens

Backfire Effect

Did belief in the corrected false claim actually become stronger, or am I calling disagreement or incomplete updating a backfire?

Evidence note Corrections usually improve factual accuracy. A true backfire effect, where a correction makes the targeted false belief stronger, appears to be uncommon and sensitive to context and measurement. It should not be treated as the default response to being corrected.

Read the evidence review · Open the decision guide