Uncovering the evidence for behavioral interventions with individuals with fragile X syndrome: A systematic review

• Reviewed 31 studies (identified by hand-search) on behavioral intervention in FXS.
• In the majority of studies, individuals with FXS showed at least some improvement.
• Overall, methodological quality of studies reviewed was moderate to weak.
• In almost half the studies, different response to intervention in FXS than ID/ASD.
• Most behavioral intervention studies were not informed by behavioral phenotype.

Fragile X syndrome (FXS) is associated with a wide range of cognitive, emotional, and behavioral difficulties. Although there is considerable research on the behavioral phenotype of FXS, few empirical studies of behavioral interventions with this population have been identified. Through a hand search of 34 behavioral journals, we examined the evidence base for behavioral interventions with individuals with FXS and in light of the current state of knowledge regarding the FXS behavioral phenotype. Systematic review procedures were used to identify behavioral intervention studies that included at least one participant with FXS, extract and summarize the data on several relevant dimensions, and rate the methodological quality of the studies. Results revealed 31 intervention studies with a small number of participants with FXS. Overall, results suggest a behavioral approach to intervention with individuals with FXS shows promise. Future research focused on individuals with FXS will be necessary to continue to examine differences in response to intervention and interventions that specifically address phenotypic characteristics.