Blood test effectively detects Alzheimer's risk before symptoms present

A blood test can detect Alzheimer's disease with 90% accuracy, outperforming traditional cognitive exams, which are correct 75% of the time and are more expensive. However, these blood tests are not yet available in doctor's offices, as further research is required to make them accessible.

What percentage of the time can someone with Alzheimer's disease be accurately identified by the new blood test?

How do traditional cognitive exams compare to the new blood test in terms of accuracy?

What is a significant drawback of traditional tests for Alzheimer's disease?

Why might the new blood tests not be readily available at doctor's offices currently?

What is needed before the new blood tests can be widely used?