Carl Heneghan director of the Centre for Evidence Based Medicine, University of Oxford responds to this weeks widely reported British researchers published in the Journal of Neuroscience who have developed a brain scan which can detect autism in adults with 90% accuracy.
To obtain a useful result, a diagnostic study needs to include a broad spectrum of the diseased, from mild to severe. A study also needs to have independent, blind comparison of test results (in this case the brain scan) with a reference standard (the current tests for autism) among a consecutive series of patients suspected (but not known) to have the target disorder and replication of studies in other settings.
But this isn’t my main concern with the reporting of the results. If they stand up to scrutiny and brain scans are adopted widely in the population it will be an expensive waste of money. In those with a positive test, autism will be diagnosed with an accuracy of only 5%, potentially leading to more harm than good.
Dr Ecker said she hoped the findings might result in a widely available scan to test for autism.
Wait a minute, what has happened? One minute the world news is reporting a test that has 90% accuracy, and I’m saying it is only 5% accurate. link to read more
Source: The Guardian
