ological issues pertaining to research involving children with autistic spectrum disorders, including information useful for describing samples; the benefits and practical problems of using randomized, clinical trial research design and the movement toward treatment comparison and aptitude-by-treatment interactions; the relative benefits and limitations of single-subject research methodology; assessing fidelity of treatment; potential use of current methodologies for modeling developmental growth of children and factors affecting growth; and group size.

There are several distinct, substantial, and independent bodies of research addressing issues concerning young children with autistic spectrum disorders. One basic body of literature describes and attempts to explain the neurological (Minshew et al., 1997), behavioral (Sigman and Ruskin, 1999), and developmental (Wetherby and Prutting, 1984) characteristics of children with autistic spectrum disorders. A second body of research has addressed issues related to diagnosis, particularly early diagnosis, of autism (Lord, 1997) and the related issue of prevalence (Fombonne, 1999). A third body of literature has examined the effects of comprehensive treatment programs on the immediate and long-term outcomes for young children with autistic spectrum disorders and their families (e.g., Harris et al., 1991; McEachin et al., 1993; Rogers and DiLalla, 1991; Strain and Hoyson, 2000). A fourth body of research has addressed individual instructional or intervention approaches that focus on specific aspects of a child’s behavior, such as social skills (McConnell, 1999), language and communication (Goldstein, 1999), or problem behavior (Horner et al., 2000). These four bodies of literature have different primary purposes (and research questions), conceptual and theoretical frames of reference, and research methodologies. However, these research literatures all have the potential of informing the design, content, and evaluation of intervention procedures.

Similarly, funding for autism intervention and educational research has also come from a number of federal institutes with separate, but overlapping missions. These include the Office of Special Education Programs (OSEP) in the U.S. Department of Education and the National Institute of Child Health and Human Development (NICHD), National Institute of Mental Health (NIMH), National Institute of Neurological Disorders and Stroke (NINDS) and National Institute on Deafness and Other Communication Disorders (NIDCD), in the U.S. Department of Health and Human Services. More recently, parent-initiated, nonprofit agencies such as Autism Society of America Foundation, Cure Autism Now (CAN), and the National Alliance for Autism Research (NAAR) have had an increasing role in supporting and instigating research.