To date, no flu vaccine has shown any significant efficacy in seniors. A 24 percent reduction in influenza illness in seniors would certainly be something to celebrate.
When medical students and residents rotate through my office, the first thing I do is hand them an article and ask them to explain the statistical methods used by the researchers. Over the years, I have had one student/doctor who understood statistics enough to understand how research articles are reported. I always tell the students/doctors that if they don't know how to properly read the original research articles, they cannot make a proper decision on whether the particular therapy is useful or not.