Inclusion Criteria:  Non-specific chronic low back pain (> 3 months) High level of psychosocial factors (a high level using the Start Back Screening Tool, i.e., cut-off of at least 4 points (total score) and at least 4 points (sub-score with questions 5 to 9)).  Exclusion Criteria:  Non-musculoskeletal conditions causing low back pain (e.g., neoplasia, infection) Neuropathic conditions (e.g., radiculopathy). Currently in litigation with paying agencies