 Dr. Macedo and others involved in the proposed research recently conducted a study that investigated whether simple clinical characteristics could identify patients who benefit more from either motor control exercises or graded activity. Motor control exercises sometimes called lumbar stabilization exercises and graded activity using the principles of cognitive behavioral therapy are two popular forms of exercise therapy with evidence of effectiveness from high quality systematic reviews, but no evidence for superiority of one approach over the other when tested in heterogenous populations. The results of a previously published study demonstrated that a simple 15-item questionnaire Lumbar Spine Instability LSI Questionnaire could identify patients who responded best to either motor control exercise or graded activity interaction 2.72 95 CI 1.39 to 4.06, p0.001. The results demonstrated that for people who are LSI negative, graded activity provided a much better outcome than motor control exercise one year post-intervention a statistically and clinically significant improvement of 1.96 points on a 0-10 numeric function scale; p 0.001. In people who were LSI positive, motor control exercise provided slightly better outcomes, compared to those prescribed motor control exercises. It is important to note that this study was measuring differences between treatments groups, and thus change in the scores of function presented represent differences between groups. 