First, if the conclusions are counterintuitive or unexpected, then when you look closer, you will find that the methodology is garbage and that it does not support the conclusions given.
Second, if the conclusions reflect things that you believe are true, when you look closer, you will find that the methodology is garbage and that it does not support the conclusions given.
If you have specific criticism regarding the methodology of this study - which doesn't, prima facie, appear unsound - please let the rest of us participate.
"The have used a correlational model, not a causal model. There are several confounding variables the paper doesn't consider, hence it is not proven from the evidence that Facebook has a negative impact "
> While many studies have found a correlation between the use of social media and various symptoms related to mental health, so far, it has been challenging to ascertain whether social media was actually the cause of poor mental health. By applying a novel research method, researchers have now succeeded in establishing such a causality
But doesn't elaborate on the new method. We'll have to wait for the study to be published I guess.
They looked at the mental health (as measured by self-reported surveys) among schools over time and cross-referenced that with the rollout of Facebook over time. So they could compare the change in mental health at schools the received Facebook access and compare it to the change in mental health at schools that did not receive Facebook access at the same time.
The methodology appears to be fairly novel and does isolate them from several reverse-causation biases, as it is difficult to imagine that the rollout of Facebook was influenced by factors that led to the decline of mental health in student bodies.