Primary Care Online Emotion-regulation Treatment (POET)

Used to assess symptom severity rated on a single item ranging from 1-7, with higher scores indicating more severe symptoms. Clinician-rated.

Used to assess symptom improvement rated on a single item ranging from 1-7, with lower scores indicating more improvement. Clinician-rated.

Used to assess symptoms of depression and anxiety. This scale has 47 items, total score ranging from 0 to 141, with higher scores indicating more severe symptoms. Clinician-rated.

Used to assess symptoms of depression and anxiety in their offspring. This scale has 47 items, total score ranges from 0 to 141 points, with higher scores indicating more severe symptoms. Caregiver-reported.

Used to assess symptoms of depression and anxiety in children and adolescents. This scale has 11 items, total score ranges from 0-33 points, with higher scores indicating more severe symptoms. Self-rated by adolescents.

Used to assess global impairment on a single item ranging from 1 to 100, with a higher value indicating better functioning. Clinician-rated.

Used to assess impaired functioning in school, everyday life, friends and social life, recreation and hobbies and family and close relationships. This scale has 5 items, total score ranges from 0 to 40, with higher scores indicating greater impairment. Clinician-rated.

Used to assess positive and negative feelings. This scale has 2 subscales. Each total subscale score range from 5-25, with higher scores indicating more negative or positive feelings. Self-rated by adolescents.

Used to assess cognitive reappraisal. The subscale has 6 items, total subscale score ranges from 6-30, with higher scores indicating greater usage of cognitive reappraisal. Self-rated by adolescents.

Used to assess difficulties in emotion regulation. The scale has 16 items, total score ranges from 16-80, with higher scores indicating more difficulties. Self-rated by adolescents.

One subscale named impulse (3 items ranging from 3-15) will be administered once every week during treatment.

Used to assesses individual differences in emotion regulation. This scale has 30 items, total score ranges from 30-180, with higher scores indicate a greater usage of emotion regulation. Self-rated by adolescents.

The three subscales named Confront unpleasant situations (3 items, total subscale score ranges from 6-18), Avoid unpleasant situations (3 items, total subscale score ranges from 6-18) and Cognitively distract (3 items, total subscale score ranges 6-18) will administered to adolescents weekly.

Used to assess alexithymia. This scale has 6 items, total score ranges from 6 to 42, with higher scores indicate higher levels of alexithymia. Self-rated by adolescents.

Used to assess social self-efficacy. The subscale named social self-efficacy has 8 items, total subscale score ranges from 8-40, with higher scores indicating greater social self-efficacy. Self-rated by adolescents.

Used to assess health-related quality of life. This scale has 9 items, total score ranges from 9 to 45, with higher scores indicating worse quality of life. Self-rated by adolescents.

Used to assess high-risk and problematic behaviors. This scale has 10 items, total score ranges from 0 to 40, with higher scores indicating greater usage of high-risk and problematic behaviors. Self-rated by adolescents.

Used to assess beliefs about emotions. This scale 16 items, total score ranges from 16 to 112, with higher scores indicating more maladaptive beliefs about emotions. Self-rated by adolescents.

Used to assess parents' perceived ability to cope with children's negative emotions. This scale has six subscales which include emotion focused, problem-focused, minimization, punitive, expressive encouragement, and distress responses. Each subscale has 9 items, total subscale score ranges from 1-7, with higher scores indicating greater usage of a certain parental coping style. Care-giver reported.

Used to assess difficulties in emotion regulation. The scale has 16 items, total score ranges from 16-80, with higher scores indicating more difficulties. Self-rated by parents.

Used to assess parents' perception of the adolescent's behavioral emotion regulation. This scale has 5 subscales. Each total subscale score ranges from 4-20, with higher scores indicating greater usage of a certain strategy. Care-giver reported.

Used to assess healthcare and other societal resource use for both children and caregivers. Caregiver-reported.

Used to assess occurrence, method, frequency of deliberate self-harm. This scale has 6 items with higher scores indicating more frequent deliberate self-harm. Self-rated by adolescents.

Used to assess treatment credibility and expectancy. The scale has 5 items ranging from 4-58 with higher scores indicating greater credibility/expectancy. Clinician-reported, adolescents self-rated, care-giver reported.

Used to assess client satisfaction with treatment. This scale has 8 items ranging from 8-32 points with higher scores indicating greater treatment satisfaction. Adolescents self-rated, care-giver reported.

Used to assess patient adherence to internet-delivered behavioral interventions. This scale has 5 items, total score ranging from 0 to 20, where 0 indicates no adherence and 20 perfect adherence. Clinician-rated.

Used to assess adverse events related to treatment. Adolescents are asked to report any negative effects or adverse events throughout the treatment period. Adolescents are also requested to report the extent of the impact of any potential adverse events on their well-being using a 0-4 scale, with a higher score indicating a more significant impact. Adolescent self-reported.

Grades in school using data from the Swedish registry Longitudinal Integration Database for Health Insurance and Labour Market Studies (LISA).

Unemployment rates using data from the Swedish registry Longitudinal Integration Database for Health Insurance and Labour Market Studies (LISA) that contains information on occupation.

Number of health care visits using data from the National (Sweden) Patient Register.

Number of psychotropic medications using data from National (Sweden) Prescribed Drug Register.

Number of mental disorders according to the ICD-10 and ICD-11 using data from the National (Sweden) Patient Register.