Should this study be trusted to support decision making? Please rate your confidence (1=lowest confidence; 10=highest confidence) in the study results. Please explain your rating

Answer Explanations

• 2

  user-481327
  Results less important than the overall design and methodology, which is mostly hampered by specific setting and low sample size. 
• 5

  user-569374
  The results differ when comparing the two different assessments of gestational fluoride exposure, where the most significant findings in the combined-sex models were seen for the estimated fluoride intake exposure variable. Conversely, maternal urinary fluoride concentration levels were less convincingly associated with IQ levels in the combined-sex models. Maternal urinary fluoride concentrations account for fluoride intake from multiple sources, not just water/beverage intake, and do not suffer the same issues with exposure misclassification as the estimated fluoride intake measure. Similarly, while maternal urinary fluoride levels were associated with lower IQ levels in males but higher IQ in females (although not statistically significant). However, this sex difference was not observed for models of fluoride intake (although stratified estimates were not presented in table 2 for these models). The discrepancy in results should be considered when considering whether they should inform decision making. That said, the magnitude of the association between maternal urinary fluoride levels and IQ scores observed among boys has the potential to significantly impact population-level IQ scores and additional research should prioritize assessing the reproducibility of these findings.
• user-868575
  N/A
• 6

  user-480186
  See above.
• 1

  user-965103
  Most importantly, the authors don't seem to realize that children born in areas with fluoridated water will continue to have increased fluoride exposure after birth. The conclusions of the study focus on exposure during pregnancy, but the observed associations may very well have resulted from exposure during the subsequent 3 to 4 years.
  From a water-fluoridation-policy perspective this may be less important, as lowering the fluoride content of the water would be the solution in either case. In terms of advice for pregnant women, or people raising small children, there could be important differences though.
  
  Further, without a clear biological explanation for the observed difference between boys and girls, and in the presence of multiple earlier studies showing no such difference, I find it doubtful that this difference is more than a chance association.
  If that's what it is, then you could also wonder whether it is chance that you do see an association in boys, or that you don't see one in girls. Either would be equally likely, casting doubt over the reliability of any conclusions from this study.
  
  In conclusion: although some tentative conclusions might be possible, these should be used solely to guide further research, as this study doesn't seem robust enough to base any kind of policy decisions on.
• 4

  user-416789
  I am not an expert in the benefits of fluoride in drinking water, but one should weigh the potential of fluoride to be associated with marginally lower IQ with the benefits of fluoride. 
• 6

  user-134615
   The results of the study are statistically significant and suggest a potential association between maternal fluoride exposure and offspring IQ. However, the confidence in these results is tempered by limitations such as sample size, potential residual confounding factors (e.g., socioeconomic status, nutrition, or other environmental exposures), and reliance on self-reported fluoride sources in some instances. These factors introduce uncertainty and reduce the robustness of the findings for broad application in public health decision-making. While the results are important and warrant further investigation, they should not be used in isolation to guide policy.
  
  

  
  
  
  
• 6

  user-603573
  The study has good sample size and it has minimised the errors of measuring urinary fluoride level by analysing 3 serial samples. 
• 4

  user-319692
  This is a preliminary / indicative study rather than a definitive one. It should lead to more studies, not practical decision-making. 
• 5

  user-2176
  Need more covariate control.
• 6

  user-881218
  Although there are uncertainties in the methods, the results seem biologically plausible.
• 2

  user-466972
  I think that's no control group 
• 2

  user-881150
  see above
• 7

  user-163602
  To some extent since there is still an element of  suspecion 
• 6

  user-368556
  Similar studies should be conducted to support the conclusion. 
• 6

  user-751579
   Perhaps, the internal validity of the study is adequate, but its external validity could be considered subject to criticism.