CINS is a large multicentre study which aims to test out the effect of 4 different interventions, namely a brief cognitive intervention (BI), a more extensive cognitive behavioural intervention (CBT), and 2 different nutritional supplementations (seal oil and soy oil) in a population of chronic low back pain patients sicklisted for 2-10 months.

The treatment principles for low back pain, and also other types of non-specific muscle pain, have changed dramatically over the last 10 to 15 years; from traditional treatment like bed rest and inactivity to more active treatment strategies ("the back pain revolution"; Waddell et al 1997). Norwegian research has been in the forefront, particularly in demonstrating the clinical and cost effective brief interventions (BI) (Indahl et al., 1995, 1998; Hagen et al 2000, 2004, Brox et al 2003, Storheim et al 2003). However, about 30% of the patients do not recover or return to normal social and working life. The aim of this study is therefore to see if a longer cognitive behavioural intervention (CBT) has an additional benefit to BI, and to compare this with a potentially beneficial dietary supplement.

Inclusion Criteria:

• Patients sicklisted 2-10 months for low back pain
• The following diagnosis are included: L02, L03, L84 and L86

Exclusion Criteria:

• Being off the sick list
• Pregnancy
• Osteoporosis
• Cancer
• L diagnoses suggesting recent low back pain trauma
• Specific spinal or other injuries which may account for the current back pain
• Serious psychiatric pathology