Table 1 Eligibility criteria

Inclusion Criteria

Rationale

  ≥18 years old

  Chronic low back pain in children results from different causes than those we are studying

  Current low back pain present on at least half the days in past 6 months

  Condition studied is specifically chronic

  Mean low back pain intensity for the previous week ≥4 on a 0 to 10 numerical rating scale (0 = no pain to 10 = worst possible pain)

  Back pain severe enough to detect improvement and prevent against floor effects

  Veteran of the U.S. military

  Defined target population

  English fluency sufficient to follow treatment instructions and answer survey questions

  Fully informed consent and data collection

Exclusion criteria

Rationale

  Significant participation in yoga in the previous 6 months

  Possible bias due to current or recent intervention users

  Read The Back Pain Helpbook in the previous 6 months

  New back pain treatments started within the previous month or anticipated to begin in the next 3 months

  Ankylosing spondylitis

  Back pain due to, or possibly result of, specific disease/condition(s)

  Active or recent malignancy

  Fracture

  Infection in or around the spine

  Pregnancy

  Other severe disabling chronic medical and/or psychiatric comorbidities deemed by the principal investigator on a case-by-case basis to prevent safe and/or adequate participation in the study (e.g., severe disabling heart failure or lung disease, psychosis)

  Comorbid condition(s) pose inappropriate risk to safety or preclude compliance with interventions

  Severe or progressive neurological deficits

  Plans to move out of the area in the next 6 months

  Known barrier to full study participation

  Lack of consent

  Research policy

  Unwilling to be randomized