Table 1. Customized self-report questionnaire of autistic traits in the general population.

1 By looking at someone’s face, I find it easy to work out what he or she is thinking or feeling (1)

2 I find it hard to make new friends (1)a

3 I enjoy social occasions such as birthdays, receptions, and so on (1)

4 I can quickly work out whether someone is fascinated by what I say (1)

5 As a child, I was a late talker or I had other speech-related problems (2)a

6 I don’t know how to keep a conversation going (1)a

7 People tell me that I keep going on and on about the same thing (1)a

8 I find making stories up easy (1)

9 I often get so absorbed in one thing that I lose sight of other things (1)a

10 It upsets me if my daily routine is disturbed (1)a

11 I prefer to do things the same way over and over again (1)a

12 I tend to notice details that others do not (1)a

13 As a child, I often retreated to my own world or I rarely played with other children (2)a

14 As a child, I moved in a rigid way or I tended to repeat certain movements (2)a

15 As a child, I often repeated the same words or I made up new words (2)a

16 As a child, I often took statements and jokes literally (2)a

17 As a child, I enjoyed playing games involving pretending with other children (1)

18 As a child, I frequently became upset by sudden and unexpected changes (2)a

The 18 questionnaire items were taken or derived from the AQ (designated with (1)) and the DSM-IV section about autism spectrum disorders (designated with (2)).

Abbreviations: AQ, Autism Spectrum Quotient; DSM-IV, Diagnostic and Statistical Manual of Mental Disorders, 4th Edition.

^aReverse-scored item.