How do you interpret a student's responses on a Schonell graded word reading test?

See the Related Links for "Schonell Reading Test" at the bottom for the first part of your answer.

So, you calculate a "reading age" from the number of Words read correctly. Compare that to the student's chronological age to see if the student is reading at level for their age, or are reading either below or above level for their age.

I've just read that the Schonell spelling test is considered out-moded, so I don't know if you should trust the results of the reading test.