Background: Efficacy in relationship to dose of spinal manipulative therapy (SMT) for the treatment of chronic low back pain has been found and previously reported. This presentation will look at cost-effectiveness across dose of SMT. Methods: We randomized 400 patients with chronic low back pain to receive one of four dose levels of care: 0, 6, 12, or 18 sessions of SMT from a chiropractor. All participants were scheduled for three visits per week for six weeks. Either the index intervention or light massage was rendered at each visit. The primary outcome was low back pain intensity. Economic analyses compare health care resources and costs for low back care, and assess the incremental costs to achieve a decrease in pain and disability scores. Results: Effects across number of intervention visits and across intervention types will be presented using incremental cost-effectiveness ratios. Regression methods commonly used in production and cost theory to measure relationships between health care inputs, their costs, and participant outcomes, while controlling for other potential confounding variables. Analysis presented will include scheduled treatment visits, all low back-related healthcare resources used outside the study reported by the patients to estimate total costs, and cost-effectiveness analysis using the EuroQol EQ-5D to evaluate quality-adjusted life years (QALYs). Conclusions: The first full-scale dose-response study of spinal manipulation has been successfully implemented. Cost-effectiveness analysis will be reported.