OBJECTIVES: To identify those symptoms and impacts with chronic low back pain (cLBP) considered by patients to be the most bothersome for the purpose of identifying relevant concepts to assess in a new patient-reported outcome (PRO) measure for cLBP. METHODS: Adults (18-80 years) with clinical diagnosis of cLBP of non-malignant origin present for at least 3 months and a current pain score ≥4 on a 0-10 numerical rating scale (NRS) were recruited from 5 U.S. clinical sites and Germany. Forty-three individual qualitative patient interviews were conducted using a semi-structured interview guide designed to elicit relevant symptoms and impacts.   At the close of the qualitative interviews, patients rated their most bothersome symptoms and most difficult impacts using a 0-10 numerical rating scale (NRS). Rating results (mean ± SD) were summarized for all symptoms and impacts using descriptive statistics. RESULTS: Participant mean age was 48.6±13.0, majority were female (53.5%) and 74.4% of participants described their racial/ethnic group as White/Caucasian (Non-Hispanic). Mean pain intensity was 6.7±1.3. Patients rated most number of symptoms they had reported as being highly bothersome on the NRS, with the highest ratings observed for - excruciating pain (9.6±0.8); sharp pain (8.7±1.3); shooting pain (8.6±1.6); electric shocks/jolts (8.0±2.0); spasms (7.7±2.7); cramping (7.5±2.4); burning pain (7.4±2.1); throbbing pain (7.0±2.4); radiating pain (6.9±2.8); aching pain (6.9±2.5); and pins and needles (6.7±1.6). The highest impact difficulty ratings included difficulty with: stairs (9.5±1.0); standing (8.4±1.8); sleep (7.9±2.3); work-related activities (7.9±2.4); walking (7.8±2.2); sexual activity (7.7±1.7); emotions (7.7±2.4); lifting (7.6±2.5); sitting (7.5±2.0); social activities (7.2±2.4); and traveling (6.8±2.2). CONCLUSIONS: Qualitative interviews identified a wide-variety of bothersome symptoms and impacts experienced by patients with cLBP. Patient-reported outcome instruments should measure those experiences, which reflect concepts most relevant to patients. Additional work is needed to assess whether items measuring these concepts are sensitive to change with treatment.