Tzaddiq, the thing is that it is know what the risk factors are for vaccinations, and more importantly what they are for not vaccinating. and let me be very clear, by not vaccinating your children you are putting them, and others around them at great risk for a number of diseases some of which can maim or kill a child.
By not giving a child vaccinations you are avoiding a totally imaginary risk at the cost of a very real one. in the days before vacines it was common for a family to have 6 kids and bury 5 of them!
There are sources that are are agreed on to be true, its called peer reviewed medical literature. We have people who are well trained to understand this stuff and to this for a living (Including our own Charlie Hall)