Table 1.

Relevant behaviour characteristics as measured by questionnaires

Questionnaire	Authors and year	Scales	Measurement
Autism spectrum quotient (AQ)	Baron-Cohen et al. 2001	AQ total	Autistic traits
Social Responsiveness Scale (SRS)	Constantino et al. 2003	Total Social awareness Social communication Social motivation Rigidity and repetition	Autistic traits
Empathy quotient (EQ)	Baron-Cohen and Wheelwright 2004	EQ total	Empathic skills
Interpersonal Reactivity Index (IRI)	Davis 1983	Personal distress Emotional concern Perspective taking Fantasizing	Empathic skills/personal distress
BIS/BAS questionnaire	Carver and White 1994; Gray and McNaughton 2000	BIS BAS drive BAS fun BAS reward	Avoidance and approach behaviour
Spielberger’s state-trait anxiety questionnaire (STAI)	Spielberger 1973	State anxiety Trait anxiety	State and trait anxiety