Please select the eligibility criteria that correspond to the clinical trial below.
Title: Effect of Yoga Vs. Stretching on Chronic Back Pain
Brief Summary: This study will compare the effectiveness of yoga classes, exercise classes, and a self-care book in the management of pain and function for people with low back pain.It will also for physical, psychological and physiological factors associated with improvement in back pain.


Options:
A: Inclusion Criteria:

* Veteran of any branch of military service
* Current low-back pain present for at least half the days over the past 6 months mean pain intensity for the previous week ≥4 on 0-10 rating scale

Exclusion Criteria:

* Significant yoga practice in the previous 6 months
* Have read The Back Pain Helpbook in the previous 6 months
* New LBP treatments started within the previous month or anticipated to begin in the next 3 months
* Known pregnancy
* Known inflammatory or systemic causes of LBP
* Severe and/or progressive medical, neurological, or psychiatric comorbidities
* Inability to understand/speak English
* Plans to move out of the area in the next 6 months
* Lack of informed consent
* Unwillingness to be randomized
B: Inclusion Criteria:

* Diagnosis of CLBP or CNP \> 6 months
* Willing to attend a yoga program for 12 weeks
* Willing to complete 3 assessments
* English literacy
* Have had no changes in pain treatments in the past month
* Willing to not change pain treatments during study unless medically necessary
* Have not practiced yoga more than 2x in the last 12 months

Exclusion Criteria:

* Back or neck surgery within the last year
* Back or neck pain due to specific systemic problem (e.g., lupus, scoliosis)
* Severe vertebral disk problems,
* Persistent sciatica or nerve compression \> 3 months
* Coexisting chronic pain problem (e.g., migraine headaches, fibromyalgia)
* Serious or unstable psychiatric illness (e.g., psychosis, mania, episode, or substance dependence)
* Major coexisting medical illness (e.g., cancer, COPD, morbid obesity)
* Positive Romberg test (with or without sensory neuropathy)
C: Inclusion Criteria:

* Group Health Cooperative enrollee
* Uncomplicated low back pain
* At least moderate pain levels

Exclusion Criteria:

* Sciatica persisting 3 or more months after physician visit
* History of cancer (other than nonmelanoma skin cancer)
* Severe disk problems
* Unstable medical conditions
* Back surgery within past 3 years
* Physically unable to do the yoga or exercise classes and homework
* Unable to attend classes
* Currently doing yoga
* Taken yoga or exercise class for back pain within past year
* Currently in litigation for back pain
* Seeking other treatment for back pain
D: Inclusion Criteria:

* 18-64 years old
* Current non-specific low back pain persisting \>12 weeks. Mean low back pain intensity for the previous week 4 or greater on a 0 to 10 numerical rating scale (0=no pain to 10=worst possible pain).
* English fluency sufficient to follow treatment instructions and answer survey questions
* Willingness to list comprehensive contact information for at least one (preferably two) friend, family member, or work colleague who will always know how to contact the participant.

Exclusion Criteria:

* Use of yoga in the previous 6 months
* New CLBP treatments started within the previous month or anticipated to begin in the next 12 months
* Pregnancy
* Back surgery in the previous three years
* Specific CLBP pathologies
* Severe or progressive neurological deficits
* Sciatica pain equal to or greater than back pain
* Active substance or alcohol abuse
* Active or planned worker's compensation, disability, or personal injury claims

Answer: C