Following the signing of a HIPPA release, the medical record will be accessed to obtain such information as: patient diagnosis, date of birth, ethnicity, number of botulinum toxin injections, muscles injected, patient weight, height, and temperature, heart rate, blood pressure and oxygen saturation during treatment, clinical description of the context of VR use; provider description of whether VR enhanced clinical care; reduction or avoidance of medication due to VR; total amounts of medications given (e.g., valium, nitrous oxide, opioids; mg/kg); and notation of patient side effects from VR. This will be done at both visits (VR and no-VR).

The Pain Opinion Questionnaire (POQ) requires caregivers to respond to 5 questions in 3 separate sections regarding children with mild, moderate, and severe/profound intellectual and developmental disabilities. A description of the abilities and limitations of a typical individual with each level of impairment is provided in each section. The questions address 5 facets of pain: (a) the ability of the children to sense painful stimuli (Sensation), (b) how upset or distressed the children feel while in pain (Emotional Reaction), (c) how strongly the children react behaviorally to pain (Behavioral Reaction), (d) how much the children communicate their pain to others (Communication), and (e) how much pain the children suffer (Frequency). We are modifying the scale to require parents or caregivers to estimate whether they believe their child (not a hypothetical child) would experience that aspect of pain the "same as", "less than", or "more than" children without impairment.

The Dalhousie Pain Interview (DPI) will provide a measure of pain experience in the previous week, including pain frequency (number of pain episodes), intensity (rated 0-10) and duration (number of seconds or minutes in pain). The measure consists of 10 items and was designed explicitly as an interview/survey script.

The Brief Pain Inventory (BPI) will provide a measure of pain interference in the previous week (i.e., the degree to which ongoing pain interferes with daily living). The BPI is a 10-item, 11-point scale (0 = does not interfere, 10 = completely interferes). The items include general activity, mood, mobility, normal work, relationships with other people, sleep, enjoyment of life, self-care, recreational activities, and social activities. Total score (sum of all 12 items combined; range 0-120) and average score (average item score; range 0-10) will be assessed.