Fibromyalgia Integrative Training for Teens (FIT Teens) is a combined coping skills training and physical exercise program. Pain coping skills training, also called cognitive behavioral therapy (CBT) teaches a number of behavioral skills (e.g. breathing, relaxation, activity pacing, distraction, and calming statements). Participants also receive a specialized type of neuromuscular exercise training which focuses on core strength, gait and balance.

Cognitive Behavioral Therapy (CBT) is a psychological coping skills training using education on gate control theory of pain, behavioral strategies such as muscle relaxation and activity pacing, and cognitive strategies including distraction, problem-solving, and using calming self-statements.

Graded aerobic exercise (GAE) utilizes a circuit-training approach with short intervals of exercise interspersed with brief rest breaks.

This intervention will consist of 16 in-person group-based sessions held twice per week over 8 weeks. Sessions last 90 minutes and will be led jointly by a psychologist/therapist and exercise trainer using manualized protocols.

Functional Disability Inventory (FDI) is a validated 15-item self-report measure, developed to assess perceived difficulty in the performance of daily activities in home, school, recreational, and social domains due to pain. Total sum scores are calculated and range from 0 - 60, with higher scores indicating greater functional disability. Clinical reference points are: No/Minimal disability (0 to 12), Mild disability (13 to 20), Moderate disability (21 to 29) and Severe disability (≥30). For this primary outcome, data from this questionnaire was used to compare baseline response to 3 month follow up to examine whether a reduction in disability occurs.

The main outcome measure for this comparison is the difference in baseline and primary endpoint (3 month) FDI scores for each of the three interventions (FIT Teens, CBT, and GAE).

Pain intensity was measured using the Visual Analog Scale (VAS), which is a validated measure of pain intensity in children and adolescents. Participants were shown a line with the written anchors of "no pain" and "pain as bad as I can imagine" on either end.

The line represents a 0-10 scale, where higher scores are representative of higher pain intensity with a score of 4-6 indicating at least moderate pain levels and a score of 7-10 indicating severe pain levels.

This measure was completed daily for one week and scores averaged over that time. For this secondary outcome, data from this measure were used to compare baseline response to 3 month follow up to examine whether a reduction in pain intensity occurred.