I am surprise that the False Positives on the March 2015 File Detection test is remaining very high, 77. The Sept 2014 test was also even higher at 120 for Avast. I also note that Avira which is usually low is now 44 compared to their Sept result of 5.
The Real World tests results show false positives in the low range.
Clearly something strange is occurring with the File Detection tests.
Does anyone have an explanation?
This topic has been explained many times in this forum. I won’t be worried about these tests at all and won’t rely on them at all. The tests that they do is that they take samples and test it with different antivirus and make a report of their findings. I have been using many paid/free antivirus in the past and I finally made a commitment to stay with Avast when they released version 7 and at present still using it. I have no regrets staying with avast, because they do an excellent job and the protection, services, and support they give to their customers is A+. The better news is that I haven’t been infected at all. I am and will be an Avast customer forever 
Thank you for your perspective.