The AQ test vs Aspie-quiz
It is claimed in publications about the validity of the AQ test by Simon-Baron Cohen that 80% of diagnosed AS will score in the Autistic range while only 2% of controls will. This seems to indicate a very reliable test with good discriminitative power.
The cutoff to “very likely Aspie” in Aspie-quiz was originally set in version 7 to provide similar properties for diagnosed AS/HFA/PDD as the AQ test (80% would get their diagnosis confirmed). The control groups in Aspie-quiz however has much higher amount of “very likely Aspie” than the AQ tests 2% (the average is around 16%). This seems to indicate much worse discriminitative power of Aspie-quiz.
To evaluate relative discriminative power between the AQ test and Aspie-quiz it is necesary to administrer both tests to the same population. This has been done twice in Aspie-quiz. The first time was in version R4 (an early experimental version) and the second was in version F1 (the first final version).
Results from R4:
- 81% of diagnosed AS/HFA score above the cutoff in the AQ test compared to 75% in Aspie-quiz (6% difference)
- 66% of all males score above the cutoff in the AQ test compared to 58% in Aspie-quiz (8% difference)
- 50% of all females score above the cutoff in the AQ test compared to 43% in Aspie-quiz (7% difference)
Results from F1:
- 59% of diagnosed AS/HFA/PDD score above the cutoff in the AQ test compared to 70% in Aspie-quiz (11% difference)
- 42% of all males score above the cutoff in the AQ test compared to 46% in Aspie-quiz (4% difference)
- 45% of all females score above the cutoff in the AQ test compared to 50% in Aspie-quiz (5% difference)
- 16% in the NT control group score above the cuttoff in the AQ test compared to 19% in Aspie-quiz (3% difference)
In version R4, the AQ test consistently gave higher scores in all groups (but primarily in the whole group and the male group). In version F1, Aspie-quiz consistently gave higher scores in all groups (but primarily in the diagnosed and female group and to a lesser extent in the whole group and the control group). These findings seems to show that Aspie-quiz has slightly higher discriminative power than the AQ test.
The correlation between score difference in Aspie-quiz and AQ score is 0.83 in both R4 and F1.
The AQ test was developped specifically with the DSM definition of AS in mind, while the intention of Aspie-quiz is to identify positive, autistic personality-traits in adults. We would thus expect the AQ test to have much better discriminative power for AS/HFA than Aspie-quiz, but this doesn’t seem to be the case. Why is this? A hint is that six questions in the AQ test has no relevance whatsoever for Autism.
These questions are:
- If I try to imagine something, I find it very easy to create a picture in my mind.
- When I’m reading a story, I can easily imagine what the characters might look like.
- I find making up stories easy.
- I am not very good at remembering phone numbers.
- I don’t usually notice small changes in a situation or a person’s appearance.
- I am not very good at remembering people’s date of birth.
Some of the above issues were early stereotypes put forward by some autism-researchers that Autistics would lack imagination, which of course is not at all true. Another 2-3 questions related to pretending also have very weak relevance.
When 12% of the questions in the AQ test lacks relevance for Autism, it is not that strange that Aspie-quiz can do a better job at discriminating AS/HFA.
The AQ test also focuses only on six of the twelve groups in Aspie-quiz’ spider-diagram. These are:
- Neurotypical social
- Neurotypical communication
- Aspie compulsion
- Aspie ability
- Neurotypical ability
- Aspie perception (one question only)
It does not have any relevant questions for:
- Aspie activity
- Aspie hunting
- Aspie communication
- Neurotypical compulsion
- Neurotypical hunting
- Neurotypical perception