A lab was used for the third setting. It allowed researches to test in a more controlled environment what they learned from the other settings.

The researchers noted that their study has implications beyond financial decision-making.

It “raises the possibility that joining an online support group sponsored by a hospital, foundation, or advocacy group may make patients choose riskier treatments or courses of action," they said. "Similarly, members of an online (or offline) adolescent club may become more likely to engage in high-risk behaviors, some of which may be detrimental, relative to comparable non-members."

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