I bet children exposed to floride in the first 10 years of life have a strong correlation to living in urban environments.
I wonder if the study was adjusted for that, or, perhaps, was it adjusted for the percent of different races?
Seems to be a fairly well designed study. It takes quite a few co-variates into consideration, including race and urban environments.
About a 3% decrease in tooth decay associated with floridation, and small increases in Autism spectrum, ADHD and Intellectual Disability.
There appear to be much larger differences between racial groups, which is considered in the analysis.