ments were analyzed in relation to their entry data to determine whether reliable predictors of treatment outcome could be identified. Both IQ scores and age of entry into treatment were found to be predictors of long-term placement. Of 11 children who entered intervention before the age of 48 months, pre- to posttreatment IQ score gains averaged 26 points, and all but one child were in regular placements (seven with support and three without support). For those who entered intervention at or older than 48 months, the average IQ score gain was only 13 points, and only one child was in a regular class placement at follow-up.

Developmental Intervention Model

Greenspan and Wieder (1997) provide a detailed review of the case records of 200 children who had participated in the Developmental Intervention Model for 2 or more years. Based on clinical notes and scores on the Functional Emotional Assessment Scale, 58 percent had “good to outstanding” outcomes, 25 percent had “medium” outcomes, and 17 percent had “low” outcomes. Overall, this pattern of outcomes was better than that of a comparison group of children who entered treatment with the Developmental Intervention Model following treatment with traditional behavioral services. However, there was a major confounding element in use of a comparison group: their parents had been dissatisfied with their previous intervention. Ratings were also not blind to intervention status. A more in-depth examination of 20 of the highest functioning children detailed marked gains on the Vineland (Sparrow et al., 1984) and CARS (Schopler et al., 1988). Somewhat inconsistent with the outcomes reported by others, expressive language scores were reported to be above those for receptive language, and self-care skills were lower than communication and socialization abilities.

Individualized Support Program

The Individualized Support Program model has reported single-subject data on the first six participating children (Dunlap and Fox, 1999a). Although this report was in a peer-reviewed journal, only one of the children’s interventions was evaluated with an experimental design. Positive pre-post changes were reported on the Autism Behavior Checklist (Krug et al., 1980), and proportional change index scores (Wolery, 1983) were computed for pre-post scores on the Battelle Developmental Inventory (Newborg et al., 1984).


The LEAP program’s effect on children’s cognitive growth (Hoyson

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