Loneliness in people with intellectual and developmental disorders across the lifespan: A systematic review of prevalence and interventions

Background The aim of the study was to conduct the first systematic review investigating the prevalence of loneliness in people with intellectual developmental disabilities ( IDD ) and the interventions targeting loneliness. Method A search across five databases was conducted (May 2016–June 2016). One reviewer (A. P.) selected the articles for inclusion and assessed their risk of bias using a standardized tool. The second reviewer (A. H.) examined the list of included/excluded articles and the ratings of the studies. Results Five prevalence studies met the inclusion criteria and provided an average loneliness prevalence of 44.74%. Only one intervention study was included, and it demonstrated that there was not any significant group difference for loneliness outcomes ( p  =   .21). The majority of the studies had a weak quality rating. Conclusion The systematic review evidenced that loneliness is a common experience in people with IDD and there is a need to extend current research.