The biggest problem with this paper, however, is in the interpretation which puts far too much weight on such weak evidence. The approach used is notoriously unreliable as a way of identifying independent associations and the lack of a clearly established prior hypothesis make it very unconvincing as evidence of a causal relationship. Given the other problems we have identified, this loose interpretation is a very serious concern. Such speculation is likely to result in unfounded public anxiety about a public health intervention which currently protects the health of children’s teeth in many parts of the world.
Water fluoridation and hypothyroidism: results of this study need much more cautious interpretation J Epidemiol Community Health. 2015 Jul; 69(7): 617–618.
Newton NN, Young N, Morris JRead Full Study