Schmerz. 2009 Jul 9; Tlach L, Hampel PBACKGROUND: The aim of this study was to investigate the criterion validity of the Mainz Pain Staging System (MPSS), considering the four axes of the MPSS separately. METHODS AND DESIGN: Psychological and pain-related impairments were analysed depending on the stage of axis (I, II, III) for each single axis of the MPSS in a consecutive sample of 280 patients with chronic low back pain in orthopaedic inpatient rehabilitation. In addition, the distribution of frequency of clinically significant symptoms in depression, anxiety and somatisation were examined depending on the stage of axis. RESULTS: For all axes, an increasing stage was associated with greater psychological and pain-related impairments. Particularly patients assigned to stage III on axis 1 (temporal aspects) and 2 (spatial aspects) and patients assigned to stage II on axis 3 (drug intake) and 4 (utilisation of the health care system) showed enhanced psychosocial impairments and more frequently had clinically relevant symptoms in psychological variables. CONCLUSION: Findings confirm the criterion validity of the MPSS for chronic low back pain. In addition, results support the significance of psychosocial factors for the further development of chronicity.
