EXAMINING PSYCHOMETRIC PROPERTIES OF THE ADOLESCENT SELF-DETERMINTION ASSESSMENT-SHORT FORM

Abstract

This dissertation consists of four chapters. Chapter 1 provides an overview of the development of theories of self-determination within special education and the emerging field of positive psychology and in the context of the how disability has been understood in our society. It also introduces The Adolescent Self-Determination Assessment-Short Form (ASDA-S) as the focus of research activities in this dissertation, and provides research questions that will be addressed in the subsequent chapter. In an initial effort to examine the psychometric properties of the ASDA-S, Chapter 2 reports reliability and construct validity data for the instrument by examining omega coefficient and three measurement invariance models using multiple groups Structural Equation Modeling (SEM). Three measurement invariance models were developed from the following samples: (a) two groups of gender, (b) seven groups of age between 11 to 22 years old, and (c) six groups of disabilities and a group of students without disabilities with adolescents and young adults. The data analyses suggested that the ASDA-S is measuring the same concept across these groups, and chi-square difference tests were conducted to examine latent mean differences across these groups. Chapter 3 examines criterion validity of the ASDA-S by examining interrelationships from the following: (a) the ASDA-S and the AIR Self-Determination Scale (AIR) and (b) the ASDA-S and the Adolescent Self-Determination Scale (ASDA; the original form of the ASDA-S). The development of higher order constructs of the ASDA-S and the AIR represented that domains statistically supported the theoretical perspectives in each measurement. In addition, the interrelationship between the ASDA-S and the ASDAS reported a strong relationship. Chapter 4 includes the conclusions of Chapters 2 and Chapter 3 and overviews implications for future research and practice of the development of collecting data from the ASDA-S.