Autism spectrum disorder (ASD) is associated with a range of comorbid psychopathology, with 70% of children with ASD meeting criteria for at least one other mental disorder 1. Furthermore, in the general population even the presence of subtle, sub-clinical ASD traits predicts the presence of additional internalising and externalising difficulties2. This suggests that mildly elevated ASD traits may be implicated in the onset and maintenance of a range of common psychological and behavioural difficulties that carry a significant cost to the individual and those around them. For example, it has recently been shown that the majority of 'severely disruptive' pupils in one UK inner city area have undetected ASD traits3.

The relationship between ASD traits and other internalising and externalising psychopathology has not been delineated in any detail, and a number of areas for investigation exist. Firstly, the cross-sectional analyses used so far cannot address the question of whether ASD traits precede the development of additional psychopathology. There is some evidence that 'social competence' in early childhood does predict later externalising and internalising problems4, but it is unclear to what extent the narrower, ASD-relevant construct of 'social-communication' (measured in ALSPAC by the Social Communication Disorders Checklist [SCDC]) precedes later psychopathology. This issue is relevant to whether or not ASD traits play a causal role in the development of non-ASD psychopathology. Secondly, nothing is known about what factors might moderate the risk conferred by elevated ASD symptomatology. Given the impact of age and gender on the type and degree of risk posed by other types of psychopathology5, it will be useful to consider these variables as potential moderators of the relationship between ASD traits and additional psychopathology. Thirdly, it is unknown whether ASD social-communication traits moderate well known pathways to psychopathology, such as the transition from oppositional defiant disorder to conduct problems6.

Data collected in the ALSPAC study offer a unique opportunity to address these issues, which are of clinical and theoretical importance. We propose using ALSPAC data for the following:

1/. An investigation of the moderating effects of gender and age on the relationship between social communication deficits and additional psychopathology. We will use SCDC data to identify individuals with consistently elevated social communication difficulties in middle and late childhood. We predict males in this group will experience an increase in their externalising psychopathology during adolescence. In addition we predict that females will experience increased internalising difficulties in adolescence.

2/. An investigation of whether social-communication abilities moderate the relationship between earlier oppositional behaviour and later conduct disorder symptoms. We aim to test this hypothesis using a cross-lagged panel design, modelling the relationships between DAWBA-measured oppositional behaviour, hyperactivity and conduct disorder symptoms at 7 and 10, and testing whether these are moderated by an individual's social-communication abilities at 7 years.

1Simonoff E, Pickles A, Charman T, Chandler S, Loucas T, Baird G. Psychiatric disorders in children with autism spectrum disorders: prevalence, comorbidity, and associated factors in a population-derived sample. J Am Acad Child Adolesc Psychiatry 2008 Aug;47(8):921-9.

2Skuse DH, Mandy W, Steer C, Miller LL, Goodman R, Lawrence K, et al. Social communication competence and functional adaptation in a general population of children: preliminary evidence for sex-by-verbal IQ differential risk. J Am Acad Child Adolesc Psychiatry 2009 Feb;48(2):128-37.

3Donno R, Parker G, Gilmour J, Skuse DH. Social communication deficits in disruptive primary-school children. Br J Psychiatry 2010 Apr;196:282-9.

4Bornstein MH, Hahn CS, Haynes OM. Social competence, externalizing, and internalizing behavioral adjustment from early childhood through early adolescence: developmental cascades. Dev Psychopathol 2010 Nov;22(4):717-35.

5Zahn-Waxler C, Shirtcliff EA, Marceau K. Disorders of childhood and adolescence: gender and psychopathology. Annu Rev Clin Psychol 2008;4:275-303.

6Rowe R, Maughan B, Pickles A, Costello EJ, Angold A. The relationship between DSM-IV oppositional defiant disorder and conduct disorder: findings from the Great Smoky Mountains Study. J Child Psychol Psychiatry 2002 Mar;43(3):365-73.