DaasYochid,
This is from the Study.
“Abstract
We use data from the Cebu Longitudinal Health and Nutrition Survey (CLHNS) in the Philippines to link vaccination in the first 2 years of life with later physical and cognitive development in children. We use propensity score matching to estimate the causal effect of vaccination on child development. We find no effect of vaccination on later height or weight, but full childhood vaccination for measles, polio, Tuberculosis (TB), Diphtheria, Pertussis and Tetanus (DPT) significantly increases cognitive test scores relative to matched children who received no vaccinations. The size of the effect is large, raising test scores, on average, by about half an SD.”
Of course, this is just a correlation, does this mean that vaccines actually make people smarter? Probably not.
This would not be a reason for one to vaccinate, nor is this part of the argument.
There might be other factors on why children whose parents decided to vaccinate them scored better. However, if the results would have been the other way around, I am sure that the anti-vaxxers would have been all over this.