PI and study coordinator both left the institution.

This study is a 10-week, randomized, parallel groups design which will evaluate the efficacy of T-ABA with combined parent training and individual child sessions versus T-ABA with individual sessions alone. T-ABA refers to Targeted Applied Behavior Analysis treatment, a form of behavior therapy used to promote skill development and reduce disruptive behavior in individuals with autism. Four key outcome assessment points will be used: baseline (week 0), midpoint (week 5), end-of-study (week 10), and follow-up (week 20). Participants receiving T-ABA parent training only will be offered eight individual therapy sessions at the end of the study. Total study participation is estimated to be ~ 10 weeks with a single follow-up assessment.

This is a ten week study. The child will be randomized to one of two treatment groups. Assignment is chosen by chance (like flipping a coin). The two treatment groups are T-ABA (Targeted Applied Behavior Analysis) with parent training and T-ABA with parent training and individual child sessions. For both groups, study procedures will be the same except the T-ABA with parent training and individual child sessions group will receive eight one-to-one Applied Behavior Analysis (ABA) individual therapy sessions during the course of the study. Participants in the T-ABA with parent training group will be offered eight one-to-one ABA individual therapy sessions at the conclusion of the study.

During the child's participation in this study families are asked to not make any changes to his or her current neuropsychiatric medications or therapy for two weeks before the study begins and during his or her ten week participation. Medication changes may include increasing or decreasing the dose you receive, changing the time of day the child takes medication, starting a new medication, or discontinuing a current medication. Therapy the child receives may include speech, OT, PT, counseling, play therapy, music therapy, social skills training, special education services, socialization, recreational sports, or nutritional interventions. Therapy changes may include increasing or decreasing how often the child receives therapy, changing who the child receives therapy from, beginning a new therapy or discontinuing a current therapy.

The child will be asked to complete assessments before the start of the study. The child will complete a language assessment and an eye tracking task that will measure his or her attention to different pictures and videos. Families will complete questionnaires that examine the child's medical and family history as well as his or her current symptoms, functioning, and quality of life and families will be given a language collection device. This is like a recorder that will record every time the family or the child talks. Families will place the language collection device in the pocket of the child's clothing and it will record the language environment for two days. Families will return the language collection device to us. To help us better understand your child's medical condition, we will access the child's medical records to collect any previous evaluations and diagnoses.

During weeks 1 through 4, families will attend a parent training group. Each group will be 1.5 hours long and will focus on topics such as discrete trial teaching (breaking skills into small components in order to teach new information to the child), natural environment teaching (using the environment to increase the child's motivation to communicate), assessing and treating challenging behavior, using visual supports and teaching everyday living activities such as drinking from a cup or washing hands. During these groups families will have the opportunity to view examples and practice using the skills discussed.

During week 5, families will attend a parent training group. Families and their children will also be observed and videotaped by study staff for 10 minutes during which they will be asked to use the techniques you learned during the parent group. The video tape will be kept in the child's study file and will only be viewed by study staff as part of the research study. Families will also complete questionnaires that examine the child's medical and family history as well as his or her current symptoms, functioning, and quality of life and will be given a language collection device (like a tape recorder). They will place the language collection device in the pocket of the child's clothing and it will record his or her language and language environment for 2 days. They will return the language collection device to us.

During weeks 6 through 9 families and their children will attend a one-hour weekly parent-therapist session with a study staff member. They will practice using the techniques from the parent group with their child and the study staff member will provide them with coaching and feedback. Families can also bring along specific questions they have.

During week 10, families will attend a parent-therapist session. Families and their children will also be observed and videotaped by study staff for 10 minutes during which they will practice using the techniques from the parent group with their child. They will also complete questionnaires that examine the child's current symptoms, functioning, and quality of life and they will be given a language collection device. They will place the language collection device in the pocket of the child's clothing and it will record his or her language and language environment for 2 days. Families will return the language collection device to us. The child will also complete testing with a study staff. Testing will measure the child's language and attention to pictures and videos during an eye tracking task.

Ten weeks after the study is complete, families and their children will complete the same assessment procedures that were completed during week 10 in order to measure any changes that occurred after the end of the study.

If a family is in the T-ABA with parent training and individual child sessions group, the child will also receive one-to-one ABA therapy sessions during weeks 1 through 4 and 6 through 9. During the one-to-one ABA therapy sessions the child may work with the therapist on skills such as making eye contact when his or her name is called, playing with toys, asking for favorite foods or activities using words or gestures, making choices, taking turns or responding to one-step commands. Study staff will work with families to select programming to be completed with their child during these sessions.

If a family is in the T-ABA with parent training group, they will be asked if they'd like to schedule eight one-to-one ABA therapy sessions at the conclusion of the study (after follow-up assessments have been collected).

Families will receive assessment results in a brief report provided after testing is completed at visits 1, 5, 10 and follow up.

Inclusion Criteria:

• Clinical DSM-5 diagnosis of Autism Spectrum Disorder (299.00).
• Age 2.0 (24 months) to 5.99 (71 months) at time of consent.
• If participant is using neuropsychiatric medication and/or receiving therapy (PT, OT, speech, ABA, etc.), these must be stable two weeks prior to their study participation and throughout the 10 week study period.

Exclusion Criteria:

• Age less than 2.0 (24 months) or greater than 5.99 (71 months) at time of consent.
• Individuals for whom neuropsychiatric medication (dose, dosing schedule, introduction of new medication, discontinuing current medication) or therapy (frequency of intervention, provider, introduction of new therapy, discontinuing current therapy) changes may occur two weeks prior to study or during the 10 week study period.
• Any participant who has previously received Applied Behavior Analysis (ABA) therapy (any form).
• Parent and/or guardian unable to speak, read and/or understand English.