Many parents have turned to St. John's wort, a herbal remedy, to treat their children with attention deficit hyperactivity disorder (ADHD). The Journal of the American Medical Association (June 11, 2008) recently published an article that explored the herb's effectiveness. Children with ADHD were randomly assigned to take either St. John's wort capsules or placebos. The contingency table below broadly reflects the results found in the study.
At the 5% significance level, do the data indicate that St. John's wort affects children with ADHD?