>a bias just means you have a preconceived view on a topic
Yes, but is it not also bias to leap to a conclusion someone is bias because they don't agree with the status quo?
> But ~40 mothers also isn't a large enough sample size.
I've spoken with many more than that over the past three decades, but I've yet to see a significantly larger sample size in any of the studies on sugar or Red 40.
>Being paid [..] is called corruption, not bias.
Of course it is, except when it's not disclosed. That is part of what the article linked here addresses. Some of those studies have been taken as being uncorrupted for decades now and that has very much influenced the current beliefs on the subject.
> I will -- there is absolutely no link
Well, I've heard too many stories about mom's taking their children to get vaccinated and describing the effects as "It's like the very next day or two their lights just went out".
I have no personal experience with this, but I won't dismiss that. There are so many variables that could affect this that it would be imprudent to do so, and those that sell vaccines are highly motivated to ignore those who've brought it up.
It's so easy to assume we know everything. It's human nature in fact to delude ourselves this way. Considering how much we do not know about how gut bugs interact with almost everything we are exposed to, that alone provides more than enough reason to avoid concrete statements like "there is absolutely no link" and doing so is most certainly proof of bias.
It's a huge leap to ignore those who witness these effects and again I can draw from my own personal experience when my first wife's doctors told me "there is absolutely no link between women having a child and psychosis". And that happened not just once, but twice.
All of her doctors, everyone of them, were arrogantly and insistently dead assed wrong and now we know they were all wrong beyond any doubt. How many moms do you think they all ignored before they finally saw the light?
It was 1 to 2 out of every 1,000 deliveries. An abortion can trigger it too.
So, if you preconceive those same odds could never apply to vaccines and autism because only 1 or 2 out of every 1,000 mom's say that was the cause you may well be wrong for a very long time even while a preventative treatment is staring you in the face.