The table below shows results from a study in which some patients were treated with fillings that contain mercury and others were treated with fillings that do not contain mercury (based on data from "Neuropsychological and Renal Effects of Dental Amalgam in Children," by Bellinger et al., Journal of the American Medical Association, Vol. 295, No. 15). Use a 0.05 significance level to test for independence between the type of filling and the presence of any adverse health conditions. Do fillings that contain mercury appear to affect health conditions?
...............................................Fillings With Mercury ......Fillings Without Mercury
Adverse Health Condition Reported ...........................135................................. 145
No Adverse Health Condition Reported .......................132 .................................122