Table 3.

Additional Exclusion Criteria Assessed at Initial Telephone Contact

1.	Previously contacted for registry participation
2.	Severe cognitive impairment that would interfere with answering questions
3.	Tumor/cancer related to the spine
4.	Any history of cancer within past 5 years, other than non-melanomatous skin cancer
5.	Spine abscess
6.	Ankylosing spondylitis
7.	Spine deformity from childhood
8.	Spine fracture
9.	Vehicular accident as cause of back pain
10.	Prior lumbar spine surgery
11.	No telephone, or planning to leave health system within next 12 months
12.	Unable to understand English