Prevalence and Risk of Sexual Violence, Dating Violence, and Sex Trafficking Among Youth with Intellectual and Developmental Disabilities

Background and Purpose: Compared to their neurotypical peers, youth with intellectual and developmental disabilities (IDD) are at a higher risk of experiencing various types of victimization, including dating violence and sexual violence. A growing area of concern is another form of victimization—sex trafficking. Although it is important to understand the scope of a social problem for prevention planning, there are several methodological challenges to determining the prevalence of sex trafficking. Suspected cases based on hotline reports are often presented as accurate estimates without substantiation, and reliance on isolated subpopulations (e.g., youth without stable housing) may underestimate the extent of the problem. Given the dearth of research pertaining to sex trafficking occurrence among youth with IDD, it is helpful to review sexual violence and dating violence more generally. This study aims to determine what is currently known about prevalence and risk of these three forms of victimization among youth (individuals up to age 25) with IDD.

Methods: A comprehensive search string and controlled vocabulary was developed in consultation with a reference librarian to identify all relevant papers published between January 2000 and January 2022 in 12 computerized bibliographic databases. Reference harvesting methods, such as using a university library search engine to find studies not indexed in the selected databases, were also used to identify articles. A study protocol was registered with PROSPERO that specified inclusion/exclusion criteria. The presenting author and two coders screened 3,597 titles and abstracts with 516 full-text studies assessed for eligibility. After double-screening, 40 studies were included. All study decisions and discrepancies were resolved through consensus.

Results: Thirty articles reported sample mean ages (M=14.76 years, SD=4.83). The most common IDD diagnoses were ADHD (n = 18), autism (n =13), and intellectual or cognitive disability (n = 11). Interestingly, some studies (n = 6) included samples of individuals with IDD who were dual victims/perpetrators. Very few (n = 6) studies provided estimates for sex trafficking, with an average of 25% of victims having an IDD diagnosis. In all but two studies with comparison data, youth with IDD were more likely to experience sexual violence than their neurotypical peers. Research focused on dating violence (n=5) only featured samples of youth with ADHD specifically; except for one study, they were not significantly found to have experienced physical dating violence more than their peers without ADHD.

Conclusions and Implications: This systematic review was conducted to summarize the literature on victimization prevalence and risk among youth with IDD, and is one of the first to present sex trafficking estimates for this population. How disability is measured and victimization reported varied greatly. One study compared reports of sexual violence from young autistic adults and their parents, finding that parents underestimated their children’s experiences. Future directions include exploring discrepancies in self- and proxy-reporting, and the high volume of cross-sectional studies calls temporality into question. Further research should also examine the nuance of dual victim/perpetrator status in violence prevention planning.