Comparison groups in autism family research: Down syndrome, fragile X syndrome, and schizophrenia.

This paper examines methodological challenges inherent in conducting research on families of children with autism and in comparing these families with others who are coping with different types of disabilities or who have nondisabled children. Although most comparative research has contrasted families whose child has autism with those whose child has Down syndrome, the range of comparison groups can be expanded to offer additional points of contrast and control. We discuss both matching and statistical control procedures and point to next steps in this line of comparative autism family research.