Looks like a straight forward article. Instead of a conclusion you are left with a discussion, which sadly is quite weak, but this seems to be the point. (As I understand it after skimming through it)

Basically you have a data set and some statistical evaluation. The gabs are filled with some medical and statistical "Mumbo Jambo" I didn't read. Seems professional, the graphs are pretty clear cut, which is nice.

The discussion basically states that the data is flawed for the purpose of making clear connections and urges the necessity to provide better data in the future. They aren't even able to make their derived call data public, due to privacy laws in this case.

They are absolute right and have a valid point here. No reason not to publish this and it conveys some important messages.

We should gather better data and find a way to share it, without touching on the privacy of individuals. A very difficult topic I personally wouldn't touch with a stick.