This week for Take-a-Test Tuesday, I took the Autism Spectrum Quotient (AQ) test. The AQ is used as a clinical screening instrument so in addition to taking the test, I read two of the studies that have been done to validate it. The write up that resulted is rather geeky.
The Autism-Spectrum Quotient (AQ) was developed by the Autism Research Centre at the University of Cambridge and first published in 2001. While the test has “Autism Spectrum” in its title, it’s geared toward identifying adults with Asperger’s Syndrome. It has been tested on adults with normal intelligence who had been diagnosed with AS or HFA*. While the AQ isn’t considered a diagnostic instrument, the 2005 study referenced later in this post did recommend that it be used by family doctors/general practitioners to determine whether to refer an adult patient for an in-depth Asperger’s Syndrome evaluation.
The AQ is composed of 50 short questions, 10 each on:
- social skills
- attention switching
- attention to detail
The 2001 study that was used to develop the AQ has some interesting data about the validity of the individual questions. If you’ve always disagreed with the idea that autistics lack imagination or can’t see the point of “the phone number question” on the AQ, you might find the individual item analysis revealing. Go take a look for yourself (Table IV, especially items 3, 8, and 29).
I’ll spare everyone else the gruesome details.
Pros and Cons of the AQ
- Short, can be taken quickly
- Includes questions phrased as both preferences and perceived competencies
- Clinically tested (statistical data available on sensitivity, specificity, test-retest reliability, internal consistency, etc.)
- Adult, adolescent and child versions are available
- Possible gender bias
- Single score outcome
- Choice of questions may be biased toward creator’s theory of autism
- No subscale scores
- Uncertainty regarding what a mid-range score might mean due to multiple recommended cutoff scores
Taking the Test
There are many places that you can take the test online. I took it at Wired.com. To get started, read the questions and choose one of the four answers for each. Don’t spend too much time agonizing over the slightly or definitely wording. The scoring is based on your choice of agree or disagree with no weight given to how strongly you feel it.
When you’ve answered all of the questions, click the “Calculate Score” button to get your AQ score. You’ll see your score on the next page along with a list of which items you scored positively on. Each positive item (i.e. item that indicates an autistic trait) equals one point, so a higher score indicates the presence of more autistic traits.
Scoring the Test
The possible scoring range is 0-50. The 2001 study found that 80% of people with Asperger’s who took the test scored 32 or higher. A subsequent 2005 study proposed a cutoff score of 26 be used when screening adults for Asperger’s in a clinical setting. The second study found that of 100 people who completed the AQ, the test correctly classified 83% of them as having Asperger’s or not. The 2005 study states that using the higher score of 32 as the cutoff would minimize false positives, so there really isn’t a clear consensus on how useful the midrange scores are.
Here is a graph comparing the scores of people with Asperger’s to the scores of neurotypical controls in the 2001 study:
The graph shows a fairly clear difference in the distribution of scores between those with Asperger’s/HFA and the control group. However, it also shows some overlap in the middle of the scoring range. Some people who were clinically diagnosed with Asperger’s/HFA scored in the teens, well below the cutoff of 32, and some neurotypical people scored in the thirties.
The original study also has some interesting outcomes for gender. In the AS/HFA group, the mean score for women was higher than for men, while in the control group, the reverse was true. In fact, the mean score for women with Asperger’s was 38.1 (vs. 35.1 for males) while not a single woman in the control group scored above 33 (highest score for male controls was 37).
Oh yeah, my score was 41.
The Bottom Line
Unless you score at one extreme or the other, you may find this test raises more questions for you than it answers.
*I used HFA (High Functioning Autism) throughout this post because it was used in the 2001 study to describe the diagnosis of some of the study participants.