Interrelationship between insistence on sameness, effortful control and anxiety in adolescents and young adults with autism spectrum disorder (ASD)

Mirko Uljarević, Amanda L. Richdale, David W. Evans, Ru Ying Cai, Susan R. Leekam

Both self-regulation and insistence on sameness (IS) are related to anxiety, which is a common feature of individuals with autism spectrum disorder (ASD). Here, we aimed to characterise the IS-self-regulation-anxiety interrelationship by investigating the potential contribution made by self-regulation, assessed via effortful control (EC), to the IS-anxiety relationship in a sample of adolescents and young adults with ASD. Seventy-one older adolescents and younger adults with ASD (49 males, 22 females; Mage = 18.71 years, SD = 2.51, range 14.42-24.81) completed the Adult Repetitive Behaviour Questionnaire-2, Effortful Control Scale of the Adult Temperament Questionnaire and the DSM-5 Dimensional Anxiety Scales. IS was associated with both EC (r = -.39, p = .001) and anxiety (r = .45, p < .001), and anxiety was in turn associated with EC (r = -.44, p < .001). To characterise the nature of this interrelationship, two mediation analyses were performed using the serial mediation model in PROCESS with 5000 resamples in bootstrapping. There was a significant indirect effect of EC on anxiety, through IS (b = -.06; BCa 95% CI [-.13, -.02]), and indirect effect on anxiety through EC (b = 1.62; BCa 95% CI [.59, 3.24]) with the mediators accounting for 29.07 and 26.04% of the total effect, respectively. Our study provides the first exploration of the IS-anxiety-self-regulation link in ASD. The finding that lower levels of self-regulation are related both to anxiety and IS behaviours points to self-regulation as a viable intervention target for both anxiety and IS behaviours.