It is estimated that 9% of adults in the United States have persistent moderate to severe noncancer pain. If the pain is untreated or inadequately treated, it has an unfavorable impact on the individual’s quality of life, leading to reduced productivity and substantial health care costs. Chronic noncancer pain is associated with conditions such as low back pain, osteoarthritis (OA), neuropathy, joint pain, and fibromyalgia. This presentation will briefly address current approaches to the treatment of persistent noncancer pain. A discussion of the issues encountered in the design of randomized clinical trials of opioid analgesics such as patient selection, enrichment procedures, dosing and titration, and use of rescue medication will be presented. The focus will also be on statistical analysis issues such as choice of efficacy endpoints, analysis methodology, and handling of missing data