Where We All Meet: ACT Approach to Adolescents Anxiety Disorders

Change in the Social Anxiety and Avoidance Scale for Adolescents

The SAASA consists of 30 items in its adapted version for late adolescents \[30\]. It intends to assess the degree of anxiety and frequency of avoidance in social situations representative of the most frequent social fears during adolescence. Each item (e.g., "Going to a party given by a colleague") is answered twice, for two subscales - anxiety and avoidance -, on a five-point Likert scale (ranging from 1 = 'none' to 5 = 'very much' for anxiety; and from 1 = 'never' to 5 = 'almost always' for avoidance). Previous psychometric information indicates very good internal consistency values, convergent validity in relation to other measures of anxious and depressive symptoms, and measurement invariance across gender and age \[30, 31\]

Change in Generalized Anxiety Disorder - 7

The GAD-7 \[32,33\] is a 7 item self-report scale initially designed to identify probable cases of Generalized Anxiety Disorder (GAD). The GAD-7 assesses Generalized Anxiety Disorder symptoms such as nervousness, uncontrollability of worry, excessive worry, restlessness, difficulty in relaxing and easy irritability. Items (e.g., "Feeling nervous, anxious or on edge") are answered in 4-point Liker scale (ranging from 0='not at all' to 3= 'nearly every day') reporting to the two previous weeks. Higher scores on the GAD-7 represent higher levels of GAD symptoms. Previous psychometric information indicates excellent internal consistency values and divergent validity in relation to measures of quality of life and satisfaction with school \[33\].

Change in the Multidimensional Psychological Flexibility Inventory - 24 (short form)

The MPFI-24 \[34\] is a 24-item self-report scale for the assessment of psychological flexibility/inflexibility, comprised by 12 subscales, representing psychological flexibility (i.e., Acceptance, Present Moment Awareness, Self as Context, Defusion, Values, Committed Action) and psychological inflexibility (i.e., Experiential Avoidance, Lack of Contact with the Present Moment, Self as Content, Fusion, Lack of Contact with Values, Inaction). Items (e.g., "I opened myself to all of my feelings, the good and the bad") are answered on a 6-point Likert scale (ranging from 1 = 'never true' to 6 = 'always true') reporting to the previous 2 weeks. The scores of the 6 flexibility and 6 inflexibility subscales can be averaged to create a composite score representing global flexibility and inflexibility, respectively. Previous psychometric information indicates good to excellent internal consistency values \[34\] . This measure is currently being adapted and validated to Portuguese adolescents.

Change in Mental Health Continuum - Short Form - for youth

The MHC-SF \[35,36\] is a 14 items self-report measure that assesses adolescent's flourishing based on levels of subjective well-being across 3 domains: emotional, social and psychological well-being. Following the instructions (i.e., "Please answer the following questions about how you have been feeling during the past month"), items (e.g., "How often do you felt happy?") are answered on a 6-points Likert scale (ranging from 0='Never' to 5='Every day'). Previous psychometric information indicates good internal consistency values and construct validity in relation to measures of quality of life, life satisfaction, anxiety, depression and internalizing and externalizing problems \[36\] .