[RogerL]

I don't see how this measures analytical capabilities.

For example, people with mild ADHD will probably fair poorly on your tests. Now, if you are hiring for something that requires profound attention to detail (dispensing medicines in a hospital), keep on. If you are trying to measure analytical abilities, you should try measuring that, not some proxy that has little to do with analytical abilities.

(and the reverse also applies - I know people with great attention to detail but that I wouldn't rate particularly highly on analytical skills).