Measurement invariance (MI) is a psychometric property of an instrument indicating the degree to which scores from an instrument are comparable across groups. In recent years, there has been a marked uptick in publications using MI in intellectual and developmental disability (IDD) samples. Our goal here is to provide an overview of why MI is…

Instruments to measure self-determination have only been available in the Spanish language to date, for adolescents with intellectual disability (ID). However, given the development of a new measure of self-determination for youth with and without disabilities, the "Self-Determination Inventory," there is a need to adapt and validate…