our guidelines (see Box 1–1 in Chapter 1). Almost all studies were pre-post designs or multiple baseline or ABAB designs without procedures to ensure blindness of evaluators to condition, as shown in Figure 1–1 in Chapter 1. About 60 percent of samples were well defined and included samples of sufficient size or replication across several subjects (see Figure 1–2 in Chapter 1). About 50 percent of the social intervention studies addressed generalization or maintenance across contexts, with 30 percent showing generalization from the teaching context to another natural situation (see Figure 1–3 in Chapter 1). This pattern reflects the commitment of most social interventions to changing behaviors in “real world” contexts, but also the difficulties of doing so with random assignments and independent evaluators blind to the intervention.
Dawson and Galpert (1990) described a pre-post study of 14 children aged 20 to 66 months and their mothers. The intervention involved teaching the parent to imitate a child in play with toys for 20 minutes each day for 2 weeks. Follow-up after 2 weeks demonstrated significant increases in the child’s gaze to mother’s face, increased number of toys played with, and increased number of play schemas used, as well as generalization to novel toys. Rogers and colleagues (1986, 1989) used a similar pre-post design to assess changes in child behavior of 13 pre-schoolers following 6 or more months of intensive intervention in a daily preschool program that emphasized positive adult-child interactions, play, and communication. Improvements in social-communicative play levels with a familiar adult, increases in child positive affect and social initiations, and decreased negative responses to mother’s initiations during mother-child play were found. The changes were interpreted as demonstrating generalization of effects from the day program. Improvement in social interactions was demonstrated across three separate measures and with various partners, adding convergent validity to the impact of this model on social development in young children with autism.
Two approaches for increasing interactions with teachers or other therapists have been demonstrated using multiple baseline approaches. One approach comes from the work of Laura Schreibman, Robert Koegel, and colleagues, using pivotal response training (PRT; see Chapter 12). Stahmer (1995) compared two interventions, symbolic play training and language training, using pivotal response techniques with seven verbal