A Study of Randomized Sham-control Auricular TENS Unit Stimulation in Pediatric Functional Gastrointestinal Disorders

EKG tracing will be used to analyze Heart Rate Variability as an indirect measure of vagal nerve output and central autonomic control.

EKG tracing will be used to analyze Heart Rate Variability as an indirect measure of vagal nerve output and central autonomic control.

Blood draw will be tested for mitochondrial function by Seahorse assay, which measures Basal Oxygen Consumption Rate of live cells to provide insight into mitochondrial activity.

Blood draw will be tested for mitochondrial function by Seahorse assay, which measures Basal Oxygen Consumption Rate of live cells to provide insight into mitochondrial activity.

Blood will be analyzed to detect changes in protein cytokine TNF α levels, an indicator for inflammation.

Blood will be analyzed to detect changes in protein cytokine TNF α levels, an indicator for inflammation

The Functional Disability Inventory (FDI) Child and Adolescent questionnaire will be used to assess change in symptoms. Participants will rank physical trouble or difficulty completing 15 different daily activities (Eating regular meals, Being at school all day, Walking up stairs, etc.) on a scale of 0-4 for each item (0-No trouble, 1- A Little Trouble, 2- Some Trouble, 3- A Lot of Trouble, 4- Impossible). Higher total scores indicate more difficulty functioning due to physical health, based on a sum score of each item. Sum score interpretation cutoffs include: No/Minimal Disability (0-12), Mild Disability (13-20), Moderate Disability (21-29) and Severe Disability (≥30).

Symptom Intensity Questionnaire score will be used to identify the most prominent 5 complaints, with intensity rated on a 10-point centimeter Likert scale. Participants write up to 5 of their most severe symptoms, and then rate those symptoms' severity from none (0) to worst you can possibly imagine (10) by placing a vertical line on the scale. Higher symptom ratings reflect higher symptom intensity & frequency. A 1-3 frequency level is a minimum level and indicates symptoms are occasional. A 4-6 frequency is a moderate level, meaning that symptoms are intermittent, coming and going. A 7-8 frequency is an indication that the symptoms are present more often than not but still not constant. A 9-10 frequency level is severe and indicates that symptoms are constant. The electronic data capture system's field validation used during the study automatically translated the participant-facing 0-10 slider scale placement into a score of 0-100, hence the reported mean values of over 10.

The Pain Catastrophizing Scale Child form (PCS-C) will be completed by the participant. The PCS-C is a modification of the adult Pain Catastrophizing Scale for use in children, measuring pain-related cognitions and the dimensions of helplessness, rumination and magnification. Participants rate how strong their feelings are about pain on a 5 point scale (0- Not at all, 1- To a slight degree, 2- To a moderate degree, 3- To a great degree, 4- All the time). Sum scores range from 0-52. Higher scores indicate higher levels of pain catastrophizing. A total PCS score of 30 represents a clinically relevant level of catastrophizing.

The Revised Child Anxiety and Depression Scale (RCADS) assesses children grades 3 to 12 containing subscales assessing for symptoms of anxiety and depression. Participants rate frequency of occurrences described in the items on a 4 point scale (0- Never, 1- Sometimes, 2- Often, or 3- Always). Sum scores of anxiety/depression items were assessed. Depression items: score range 0-30 Anxiety items: score range 0-18 Higher scores on both the depression & anxiety items indicate higher levels of depression & anxiety. Raw sum scores of both the depression & anxiety subscale items are translated to a T-score. T-scores below 65 represent low severity. T-scores between 65-70 represent medium severity and are on the borderline clinical threshold. T-scores above 70 represent high severity and are above the clinical threshold. A T-score of 50 indicates the population mean with a standard deviation of 10.

The Functional Disability Inventory (FDI) Parent questionnaire will be used to assess change in the participants symptoms as rated by the participants parent/guardian. Parents will rank their child's physical trouble or difficulty completing 15 different daily activities (Eating regular meals, Being at school all day, Walking up stairs, etc.) on a scale of 0-4 for each item (0-No trouble, 1- A Little Trouble, 2- Some Trouble, 3- A Lot of Trouble, 4- Impossible). Higher total scores indicate more difficulty functioning due to physical health, based on a sum score of each item. Sum score interpretation cutoffs include: No/Minimal Disability (0-12), Mild Disability (13-20), Moderate Disability (21-29) and Severe Disability (≥30).

The Pain Catastrophizing Scale Parent form (PCS-P) will be completed by the parent or guardian of the participant. The PCS-P is a proxy questionnaire to the PCS-C, measuring the feelings the parent has when their child is in pain. Parents rate how strongly they feel when their child is in pain on a 5 point scale (0- Not at all, 1- To a slight degree, 2- To a moderate degree, 3- To a great degree, 4- All the time). Sum scores range from 0-52. Higher scores indicate higher levels of pain catastrophizing. A total PCS score of 30 represents a clinically relevant level of catastrophizing.