Flexible Attention Sensory Training for Youth with Chronic Pain

Acceptability will be evaluated by examining mean promoter score (measured on 10-point Likert scale) post intervention. Range 0-10 (higher scores indicate more acceptability). Questionnaire will be administered to youth with chronic pain.

Acceptability will also be assessed qualitatively at the end of treatment through interview questions related to acceptability, ease of use, comprehensibility, and suggestions for improvement. Survey responses will be reported categorically. Qualitative responses will be described and summarized.

Acceptability will also be assessed quantitatively at the end of treatment through a brief survey related to acceptability, ease of use, comprehensibility, and suggestions for improvement. Survey responses will be reported categorically. Responses are measured using a five-point Likert scale from 'Strongly disagree' to 'Strongly agree' with higher scores indicating greater acceptability.

Engagement will be assessed via collected use metrics (e.g. how long the app was played each day).

The Brief Pain Inventory evaluates the severity of a patient's pain and the impact of this pain on the patient's daily functioning. Measured on a 10-point Likert scale (range 0-10), higher scores indicate greater pain interference. Questionnaire will be administered to youth with chronic pain.

Bodily threat monitoring will be assessed via a 19-item self-report measure. Higher scores indicate greater propensity to monitor the body for threatening signs and symptoms.

Single question asking participants to rate how their condition has changed since a specified point in time, with lower scores indicating greater degree of improvement.

The PVAQ is a 16-item measure of attention to pain. Participants are asked to consider behavior over the past 2-weeks and indicate how frequently (0, never; 5, always) an item was true. Higher scores indicate higher pain vigilance and awareness.

Child report on the Chronic Pain Acceptance Questionnaire for Adolescents-short form will be used to assess pain acceptance in the child. The CPAQ is an 8-item measure consisting of two subscales: Activity Engagement (4 items) and Pain Willingness (4 items). Items are rated on a 5-point Likert scale ranging from 0 (Never True) to 4 (Always True) and yield a total score for each subscale ranging from 0-16. Higher scores indicate greater Activity Engagement and greater Pain Willingness.

The MAIA-Y is an 8-scale state-trait questionnaire with 32 items. It measures multiple dimensions of interoception. Scoring is at the individual scale-level, with higher scores equated with more bodily sensation awareness. The individual score is also given as a percentile relative to normative sample, with extreme percentiles (>10, 90<) of clinical significance. Three scales from this measures are being administered: Attention Regulation, Self-Regulation, Trusting.

The Revised Life Orientation Test will be used to assess self-reported optimism in the child. The LOT-R is a 10-item measure yielding a total score ranging from 0-20 (only 5 items are utilized in the final score calculation). Higher scores indicate greater optimism.

The Childrens Hope Scale will be used to assess self-reported hope in the child. The CHS is a 6-item measure yielding a total score ranging from 0-36, with higher scores indicating greater hope/

The Pain Catastrophizing Scale -Child Version (PCS-C, Crombez et al., 2003) assesses negative cognitions associated with pain. The PCS-C is comprised of 13-items rated on a 5-point Likert scale (0= "not at all true" to 4 "very true"). A total score (0-52) is obtained by summing all items. Higher scores indicate higher levels of catastrophic thinking.

We are administering an additional 13-item weekly diary, developed by our group, which measure self-reported fear, avoidance, functioning, activity engagement, pain reactivity, and attention.

The Parent Psychological Flexibility Questionnaire (PPFQ-10, Timmers et al., 2019) is a 10-item parent self-report questionnaire assessing a parent's ability to accept their own distress and respond adaptively and flexibly to their child's pain. Items are rated on a 5-point Likert scale (0= " never true" to 4 = "always true") and are summed to create a total score, ranging from 0 - 40. Higher scores indicate greater parent psychological flexibility.

Pain Catastrophizing Scale-Parent Version (PCS-P, Goubert et al., 2006) assesses parents' negative cognitions associated with their child's pain. It is comprised of 13 items rated on a 5-point Likert scale (0 = "not true at all" to 4 = "very true"). A total score (0-52) is derived by summing items, with higher scores indicating higher levels of catastrophic thinking.

Participants (child) and parent expectations for treatment will be measured by the Treatment Expectancy and Creditability. The TEC is comprised of 6 items rated on a 0 to 10 Likert-scale assessing expectations related to the effectiveness of the current treatment. The TEC is completed by the patient at the end of the first treatment session and at the end of treatment (8 weeks). Higher scores indicate greater expectations for treatment effectiveness.