The real takeaway should be that children who are doing little reading, or who start reading late, should be given whatever kind of reading they are willing to do: comic books, series books, graphic novels--whatever they will read.
I taught in an inner-city Catholic school and found that--when I stocked my room with comics and magazines and high-interest paperback, and told my poor readers just to sit and read--they gained an average of 18 months of reading ability for every 6 months I had them in that program. In a regular class, they had been gaining about 3 months of skills every 6 months.
While one-on-one intensive tutoring may help, there is no substitute for very high-interest reading material. And once a kid becomes hooked on reading, his reading scores soar, and he will become a lifelong reader.