This study will compare the effectiveness of two parent-based programs for helping young children at risk of autism.

Autism is a problem with normal social development and is characterized by impairments in three categories: social skills, language, and behavior. Symptoms include disinterest or inability to have normal social relationships, abnormal speech or usage of phrases, and repetitive movements or rituals; these symptoms generally emerge by 18 months of age. Autism is a spectrum disorder, meaning that its symptoms can range in severity from mild to severe. There is no cure for autism, nor is there a single known cause. There are only factors known to make it more likely for children to develop autism. These include being a male, having siblings with the disorder, having certain other disorders, or having an older father. Treatments for autism generally include therapies that help children develop social communication skills and that help structure family time and school so that parents and teachers can address particular difficulties children with autism might have. Medications may also be used to counteract anxieties or compulsive behaviors.

Research has shown that earlier interventions in children who are at risk of autism may lead to better outcomes. This study will compare two interventions for developing social communication skills in children who are at risk of autism and are between 16 and 20 months old. The parent-implemented intervention (PII) will be a more intense, individualized approach, teaching parents to embed 25 hours of social communication skills practice per week in their children's daily lives. The information, education, and support (IES) intervention will offer parents a support group and place to practice methods of helping their children learn adaptive social communication.

Participation in this study will last 18 months. Participants will be randomly assigned to first receive 9 months of either PII or IES and then receive 9 months of whichever intervention they did not receive initially. The PII intervention will involve three weekly sessions for 7 months, then two weekly sessions for 2 months. The IES intervention will involve group meetings twice monthly and offer a playground where parents can practice intervention strategies with their children. All parents will complete questionnaires about family resources and social and emotional issues before the first intervention begins, after 9 months when the intervention changes, and after 18 months when the second intervention ends. Children and parents will also be assessed once a month throughout the study on social communication, autism symptoms, developmental level, and hours spent on learned strategies or techniques outside the study visits. These assessments will involve clinical assessments of parent and child behaviors (some of which will be videotaped), tests of children's abilities, and reports by parents on strategies and techniques used outside the clinic.

• Behavioral: Early Social Interaction Project- PII
• Behavioral: Early Social Interaction Project- IES

• Experimental: This group will first receive the Early Social Interaction Project parent-implemented intervention (PII) for 9 months, followed by the Early Social Interaction Project information, education, and support (IES) intervention for 9 months.
• Experimental: The group will first receive IES for 9 months, followed by PII for 9 months.

Inclusion Criteria:

• Presence of autism risk factors and a clinical diagnosis of autism spectrum disorder based on a diagnostic evaluation conducted by the project team
• Normal hearing and adequate motor control to make simple actions, such as giving and reaching
• Families agree to twice monthly play group sessions for 9 months and two to three intervention sessions per week for 9 months, usually to be scheduled within workday hours
• Families agree to monthly evaluations, videotaping of intervention sessions, and weekly or monthly video checks during the 18 months of treatment