From my years of experience working with students taking the DAT, many where English is a 2nd language and some a 3rd language, I stress the importance of just old fashion reading. You can read books, new papers, etc, anything you like. I feel it's best to go back to old school style reading with an actual book, etc. All students have experience reading from a computer screen. The goal is to increase reading speed and comprehension. With sharp skills in these 2 areas, you should be able to tackle any passage you will see on the DAT. IMO, taking tests and only reading a few articles will not help you improve.
Things have changed a lot over the years with cell phones, etc and students do not read as much in general compared to past generations. This is what I suggest, get any reading material you prefer(on a college level) and put it by your bed. Put away the cell phone, computer and read at least 30 minutes each night, it is very relaxing and you will be improving your skills at the same time.
A recent student I advised where English was his third language scored 22 in reading.
If you use this technique it will feel less overwhelming and you can do a little each day.
Just my 2 cents
Nancy