Background and aims: To evolve the efficacy of pain treatments, we need to describe chronic pain conditions in their most relevant aspects, and have real-world outcomes of clinical interventions. This insight is best obtained through analyses of data from large registries where patient characteristics, treatment characteristics, treatment outcomes and patient outcomes are recorded.
Methods: This study describes the design and baseline data of the Oslo University Hospital Pain Registry (OPR). OPR is the local registry of the largest university and interdisciplinary outpatient pain clinic in Norway. Recording of patient data started in October 2015, with approximately 1,000 patients were assessed and treated at the clinic yearly. During the 2 years of running, 1,712 patient baseline reports were recorded from 2,001 patients. Clinicians enter data about relevant treatments and interventions. The patients complete an electronic registration immediately before their first consultation at the outpatient pain clinic. The baseline questions of the OPR cover: Basic demographics; Pain characteristics; And biopsychosocial aspects (i.e., quality of life, distress, self-efficacy, fatigue, sleep, pain catastrophizing, experienced injustice). 
Results: Baseline data show that chronic pain patients experience a large negative impact in all aspects of life.
Conclusions: The OPR describes relevant aspects of chronic pain conditions, and efficacy of interventions in a real-world setting. The OPR may serve as a registry model for other pain clinics, and the OPR cohort may also serve as a historical control in future studies.

THE OSLO UNIVERSITY HOSPITAL PAIN REGISTRY: A DIGITAL REGISTRY WITH BASELINE DATA FROM 1,712 CHRONIC PAIN PATIENTS