BMC Public Health 2009, 9:251 http://www.biomedcentral.com/1471-2458/9/251 Referral of patients, inclusion criteria: • Between 18 and 65 years • Being able to speak, read and write Dutch • UPS at least 6 months Informed consent of patients: • Interview to inform patient about study • Signed informed consent Assessment of eligibility: • SCID I: -undifferentiated somatoform disorder or -pain disorder Assessment of personality: • VKP Baseline outcome measurement Randomization Group training Outcome measurement Follow-up measurement I 3 months after training Follow-up measurement II 12 months after training Dropout: • Losses Dropout: • Losses Dropout: • Losses Dropout: • Losses FDiegsuigrneo1f the randomized controlled trial Design of the randomized controlled trial. Dropout: • Losses Dropout: • Losses • No informed consent Dropout: • Losses • Ineligibility Dropout: • Losses Waiting list Outcome measurement Group training Follow-up measurement I 3 months after training Follow-up measurement II 12 months after training Page 3 of 9 (page number not for citation purposes)