Psychometric Properties of Acceptance and Action Questionnaire-II in U.S International College Students: An Item Response Theory Analysis

Background and Purpose: During the 2020/2021 academic school year, there were 19,744,000 international students enrolled in U.S. schools (International Education, 2022). International students' transition and adjustment to the United States confront them with various stressors, such as linguistic difficulties, social isolation, and cultural barriers, each of which impacts their mental health(Lian & Wallace, 2020). Psychological inflexibility has been identified as one of the transdiagnostic factors associated with various mental health conditions, i.e., depression, PTSD (Levin et al., 2014; Mulick et al., 2005). Experiential avoidance, the unwillingness to remain in contact with uncomfortable private experiences, for example, negative thoughts or feelings, is related to psychological inflexibility. The ability to assess and develop interventions and social support that will promote experiential avoidance would support the well-being of students. The Acceptance and Action Questionnaire II (AADII) was developed to experiential avoidance based on the original Acceptance and Action Questionnaire measure (Correa-Fernández et al., 2020). While differential item functioning (DIF) has been carried out with university students(Correa-Fernández et al., 2020; Edwards & Vowles, 2020), there is an examination of the measure's validity with international students, those with and without mental health concerns.

This research aims to: 1) explore the psychometric properties of AAQ-II in U.S international college students; 2) explore whether AAQ-II function similarly across international students with and without mental health conditions.

Methods: Data and samples. We use the 2019-2020 Health Mind Survey (HMS). Our sample consists of 1551 international students who completed the entire survey. Among our sample, 322 students had mental health diagnoses before.

Measures. AAQ-II. AAQ-II is a seven-item unidimensional scale measuring psychological inflexibility. Items are rated on a 7-point scale ranging from “1 = never true” to “7 = always true”.

Analytical Plan: IRT Graded Response and 2PL Models were used to examine the properties of the general AAQ-II scale and the item-level fit in international college students. Then we use Differential Item Functioning (DIF) to assess the function of AAQ-II across international students with and without mental health conditions.

Results: The most reliable item for international students with mental health conditions was item 4; however, the most reliable item for students without mental health conditions was item 3. The Test Information Function also indicated that the AAQ-II differentiates international students with mental health conditions well around the theta mean. But, the scale was more reliable for students without mental health conditions, around two standard deviations above the theta mean.

Items 2, 3, and 6 exhibited differential item functioning, which means that those items performed differently across students with and without mental health conditions.

Conclusions and Implications: For international college students, they understand the AAQ-II differently, and the measure functions differently across students with and without mental health conditions. We should notice the cultural difference in students’ perceptions and not only rely on survey results to evaluate students' mental status. Social workers should advocate for flexible mental health services based on students’ needs.