Yours seems like a flippant response, but I don't think that it is. We have to be wary of confirmation bias here on HN. Would someone even think to publish a study where no effect was found? And then would someone post that link to HN? And then would it get upvoted? It's important to remember that we are not seeing a uniform sample of news stories here. We are seeing a highly biased selection, and it's important to appropriately discount things appropriately.