In 1998 the Dutch Study Group on Child Spasticity designed the Dutch national study on the effectiveness and safety of ITB for refractory spasticity in children with cerebral palsy. The Dutch national ITB study included four phases: 1] the selection phase, 2] the double-blind, placebo-controlled dose-escalation test treatment phase, 3] the prospective, randomized, open-label implantation phase and 4] the follow-up phase.