OK, I agree totally with you, that this study wasn't powered enough to answer a question about causal relationship between Asthma and watching TV. I have also first thought
... OK, this newsflash comes from yellow magazines
... but it doesn't !
They do actually comment it on their web site: http://www.bristol.ac.uk/alspac/documents/tv-asthma-risk.pdf
And this link is the first link on the front page of the study. They are just not serious and this is not something so uncommon in academic circles these days
... They just push such "news" . Plain ugly. Maybe because the other data they mined with taxpayers money was so less interesting, they didn't bother to talk about it. They add, that sun is good for mum and the baby and that FTO is linked to increased appetite
... and the input data was collected form mother reported survey
Why do they still throw money on such studies with total lack of scientific imagination ?
THe cause: YES, WE CAN !!
And they do it. They get a big budget from the country and then they do the "research". But the bill has come and also UK will have to find a way to think, where will they pounds be spend. They didn't bother till now
... and now they CAN'T any more