The grades of recommendations (standards, guidelines, and options) and classes of evidence (I–III) are defined at the end of the "Major Recommendations" field.
Standards. Lumbar fusion is recommended as a treatment for carefully selected patients with disabling low-back pain due to one- or two-level degenerative disease without stenosis or spondylolisthesis.
Guidelines. There is insufficient evidence available to support a treatment guideline.
Options. An intensive course of physical therapy and cognitive therapy is recommended as a treatment option for patients with low-back pain in whom conventional medical management has failed.
Summary
Class I medical evidence exists in support of the use of lumbar fusion as a treatment standard for carefully selected patients with low-back pain intractable to the best medical management. There is Class III medical evidence that suggests that a course of intensive cognitive and physical therapy may be an efficacious treatment option for the treatment of patients with chronic disabling low-back pain.
Definitions:
Grades of Recommendation
Standards Recommendations of the strongest type, based on Class I evidence reflecting a high degree of clinical certainty
Guidelines Recommendations based on Class II evidence reflecting a moderate degree of clinical certainty
Options Recommendations based on Class III evidence reflecting unclear clinical certainty
Classes of Evidence
Class I Evidence from one or more well-designed, randomized controlled clinical trials, including overviews of such trials
Class II Evidence from one or more well-designed comparative clinical studies, such as nonrandomized cohort studies, case-control studies, and other comparable studies, including less well-designed randomized controlled trials
Class III Evidence from case series, comparative studies with historical controls, case reports, and expert opinion as well as significantly flawed randomized controlled trials