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Pwent
Guest
Pew is pretty good. Most of their studies that I have looked at thoroughly were US only, so I don't know much about how they structure international polling, but in general I'd say they are trustworthy.
pew themselves are mostly trustworthy, ive seen some "surprising" results that dont match up with any other sources
i just always check the study because sometimes people repost them under different headlines that dont 100% line up with the actual polling or methodology