The aim of this study was to determine the prevalence of autistic spectrum disorder (ASD) within a large representative population sample: the Avon Longitudinal Study of Parents and Children (ALSPAC). Cases of ASD were identified from the clinical notes of children in the ALSPAC with a suspected developmental disorder and from the Pupil Level Annual Schools Census (PLASC) for England in 2003. Seventy‐one cases of ASD diagnosed after a multidisciplinary assessment were identified from health records. There were an additional 15 cases from PLASC data in which ASD was mentioned as a principal difficulty, thus giving a total of 86 children diagnosed by the age of 11 years. Prevalence of ASD per 10 000 population at 11 years was 51.1 for those with a multi‐professional diagnosis, and 61.9 if cases from education were included, made up of 21.6 for childhood autism, 10.8 for atypical autism, 16.6 for Asperger syndrome, and 13.0 for unspecified ASD. The male:female ratio was 6.8:1. Median age at diagnosis ranged from 45 months in childhood autism to 116 months in Asperger syndrome. A comorbid developmental disorder was recorded in 33.8% of cases, including learning disability* in 14.7%, epilepsy in 10.3%, and mixed developmental disorder in 4.4%. We conclude that the prevalence of ASD diagnosed at 11 years in a UK representative population‐based sample is at least 51.1/10 000.

Everyday humour and laughter can tell us about children's ability to engage with and understand others. A group of 19 pre-school children with autism and 16 pre-school children with Down's syndrome, matched on non-verbal mental age, participated in a cross-sectional study. Parental reports revealed no group differences in overall frequencies of laughter or laughter at tickling, peekaboo or slapstick. However, in the autism group, reported laughter was rare in response to events such as funny faces or socially inappropriate acts, but was common in strange or inexplicable situations. Reported responses to others' laughter also differed: children with autism rarely attempted to join in others' laughter and rarely attempted to re-elicit it through acts of clowning or teasing. Analysis of videotaped interactions also showed no group differences in frequencies of child or adult laughter. However, the children with autism showed higher frequencies of unshared laughter in interactive situations and lower frequencies of attention or smiles in response to others' laughter. Humour is an affective and cultural phenomenon involving the sharing of affect, attention and convention; children with autism show problems in some simple affective and mutual as well as joint attentional and cultural aspects of humorous engagement.

Evidence that interpersonal interactions and self-appraisal in social context are crucial in developing self-understanding raises concerns about how pupils with autism spectrum disorder make sense of themselves in school settings where many experience social marginalisation. Metasynthesis was used to systematically extract and integrate findings from qualitative studies examining the mainstream school experiences of these students. Synthesised findings identified three, intermeshing, aspects of experience which contribute to many pupils with autism spectrum disorder making sense of themselves as 'different' to typical peers in a negative way: difficulties linked to autism spectrum disorder; interpersonal relationships, particularly with peers; and accessibility of the school environment. Typical pupils' attitudes and responses towards peers with autism spectrum disorder, unusual sensory reactions to the physical school environment and individual sense-making about the self are highlighted as key areas requiring further research and intervention to improve the experiences, self-esteem and well-being of pupils with autism spectrum disorder in inclusive settings and to inform educational policy and practice.

The article reviews the empirical evidence relating to the development of early solitary object and parent-infant play in typical infants and children diagnosed with autism. Whilst, collectively, the findings indicate that there may be both qualitative and quantitative differences in the early play of children with autism, relative to that of other children, it is also clear that significant gaps exist in our current knowledge. It is proposed that longitudinal studies, which make a detailed examination of the form and developmental trajectory of early play, are needed if we are to devise the most effective content, design and outcome measures for intervention programmes using play as a therapeutic medium.

Research evidence indicates that children with autism may experience problems with functional play, in addition to their well-documented deficits in symbolic play. However, as a result of the tendency of previous studies to group all functional play into a single category, the precise nature and extent of this deficit remains unclear. The present study undertook a more refined analysis of such play, subtyping the functional acts into various categories, in terms of the developmental progression suggested by research with typical infants. The functional play of children with autism was compared to that of developmentally matched children with Down syndrome and typical infants. Although there were no group differences in overall measures of the proportion of total play time spent in functional play and in the number of functional acts performed, a closer analysis of the composition of this play did reveal striking, qualitative differences. The functional play of the autism group was less elaborated, less varied, and less integrated than that of the controls. The implications of these findings are explored in relation to current theoretical models of autism and in relation to the role of other people in mediating the appropriate use of objects.