The theoretical basis for MET and the exercise progressions have been described in scientific articles and book chapters. Self-assessed pain, function and quality of life are monitored both during treatment and after treatment, and at six and 12 months follow-up. Prognostic markers evaluated by following analyze background information and early test results relate to the long-term treatment outcome. Analysis of cost-effectiveness will be done using the incremental cost-effectiveness ratio (ICER), in order to provide a single measure for weighing costs against effects of the exercise dosage interventions. An assessment will also be made for the cost per quality-adjusted life year (QALYs).