Deficits in communication in people with disabilities are a major cause of challenging behaviors. Functional communication training (FCT) is one treatment developed to address both challenging behavior and instruction in replacement communicative behaviors by determining the function, or reason, the behavior occurs and developing a communication intervention to address that function. This meta-analysis included 36 single-case studies that evaluated the impact of functional communication training on challenging behaviors in people with disabilities. Effects were measured using the Robust IRD effect size. Findings indicate that functional communication training has strong effects overall. Regarding communication mode, results were greater for speech (verbal) than aided augmentative and alternative communication (AAC) and greater for aided AAC than unaided AAC. Further, primary-aged participants had stronger effects than elementary-aged children and elementary had better effects than adults. Secondary students also had better effects than adults, though effects for secondary-aged participants were not significantly different than those for primary or elementary ages. Finally, FCT was more effective with participants with autism than intellectual disabilities. Challenging behaviors such as aggression, self-injury, stereotypy (e.g., repetitive hand movements or speech), and noncompliance are common in individuals with autism spectrum disorder (ASD), intellectual disabilities (ID), and multiple disabilities (Baghdadli, Pascal, Grisli, and Aussiloux 2003;Kiernan and Kiernan 1994;McClintock, Hall, and Oliver 2003;Murphy et al. 1999;Poppes et al. 2010). If severe and chronic challenging behavior is not addressed, individuals with disabilities are at risk for poor academic achievement, adult mental health concerns, and peer rejection (Dunlap et al. 2006). Challenging behavior also puts individuals at higher risk for abuse, neglect, deprivation (Emerson et al. 2001;Lowe et al. 2007), victimization (Crocker et al. 2006;Rusch et al. 1986), and incarceration (Lund 1990;Crocker and Hoggins 1997;Crocker et al. 2006). Many of these risks can be linked to restrictive social and learning environments due to said challenging behaviors (Buschbacher and Fox 2003;Machalicek et al. 2007;Reichle 1990). Individuals may be segregated or excluded to institutions or specialized treatment centers due to these behaviors, and services within these more restrictive settings can be inconsistent and inadequate due to a higher rate of staff turnover (Hastings and Brown, 2002;Lowe et al. 2007;Machalicek et al. 2007). To decrease the risk of segregation and serious emotional issues, challenging behavior must be addressed using consistent implementation of evidence-based practices.Prior to the mid-1980s, a majority of the research on behavioral interventions for challenging behavior focused on reactive approaches, for example, punishment or withholding reinforcement (Carr 1985;Carr and Durand 1985). Time-out (Zeilberger, Sampen, and Sloane ...
