Table 1.

Eligibility Criteria for the SWIFT Trial

Inclusion criteria	Exclusion criteria
Patients with chronic (≥3 months) or recurrent (≥3 episodes in previous 12 months) LBP of mechanical origin with/without radiation to the lower limb	Currently or having received treatment for CLBP within previous 3 months
Males/females between 18–65 years	Red flags indicating serious spinal pathology, e.g. cancer, cauda equina lesion
No spinal surgery within the previous 12 months	Radicular pain indicative of nerve root compression
Patients deemed suitable by their GP/hospital consultant to carry out an exercise programme	Patients diagnosed with severe spinal stenosis, spondylolisthesis, fibromyalgia
Patients willing to attend for an 8-week treatment programme of exercise classes	History of systemic/inflammatory disease, e.g. rheumatoid arthritis
Access to a telephone (for follow-up support)	Patients with any confounding conditions such as a neurological disorder or currently receiving treatment for cancer
Fluency in English (verbal and written)	Patients with acute (< 6 weeks) or subacute LBP (6–12 weeks), provided that they have experienced < 3 LBP episodes during previous 12 months
'Low' or 'moderate' levels of physical activity measured by the IPAQ (< 600 MET-minutes/week)	Unstable angina/uncontrolled cardiac dysrhythmias/severe aortic stenosis/acute systemic infection accompanied by fever
	Medico-legal issues
	Pregnancy