The Journal of Manipulative and Physiological Therapeutics 2004 conducted a randomized controlled clinical trial of 160 outpatients with acute or subacute low back pain. Patients were randomly allocated to a reference group and an experimental group. The reference group was treated with the “stay-active” concept. The experimental group received manual therapy in addition to the stay-active concept. At baseline, the experimental group had somewhat more pain, a higher disability rating index and more herniated disks than the reference group. Results showed that – after five and 10 weeks – the experimental group had less pain and a lower disability rating index than the reference group.