Measuring psychological flexibility across the lifespan: validation of the Adult and Adolescent Psychological FlexibiliTy Scale (ADAPTS)
Year: 2025
Type: dissertation
Abstract: Psychological flexibility is regarded as a key component of mental wellbeing. It is the proposed mechanism of change underpinning Acceptance and Commitment Therapy (ACT) and is thought to be composed of six core processes: acceptance, present moment awareness, defusion, self-as-context, values, and committed action. These are further grouped to form the triflex processes of openness to experience, behavioural awareness, and valued action. Psychological inflexibility is the inverse of psychological flexibility involving experiential avoidance and cognitive fusion and has been found to have associations with poor mental health outcomes. Accurate measurement of constructs thought to underpin mental wellbeing, such as psychological flexibility, is key to the evaluation of interventions and development of recommendations regarding treatment for mental health difficulties. The AAQ-II is a widely used measure of psychological flexibility in ACT research. However, it has been noted to not provide a comprehensive measure of the six proposed core processes and demonstrates multicollinearity with anxiety scores. The AFQ-Y is a youth measure of psychological flexibility developed from the AAQ-II. The Adult and Adolescent Psychological FlexibiliTy Scale (ADAPTS) has been developed in order to address some of the issues found with existing measures and provides a comprehensive measure of psychological flexibility across youth and adult populations. The ADAPTS uses plain English making it appropriate for those who could benefit from accessible language. Exploratory factor analysis (EFA) was used to understand the structure of the ADAPTS in youth and adult samples. The ADAPTS was also compared to existing measures to assess concurrent, convergent, and discriminant validity. EFA indicated a three-factor structure (Openness to experience (5 items), behavioural awareness (5 items), and valued action (8 items)) across 18 items for the ADAPTS in both populations. The ADAPTS demonstrated good concurrent, convergent, and discriminant validity across both populations. Subscale validity for the three factors is provided and further project data, analysis, and materials are provided in the extended paper. This project supports the ADAPTS as an accessible, reliable, and valid measure of psychological flexibility for use across the lifespan in both clinical and research settings.
Author: Agrippa, Safia
Language: English
Subfield: Clinical Psychology
Field: Psychology
Domain: Social Sciences
Open Access status: green
OpenAlex ID: W7114939833