An important and widely used instrument to assess psychosocial function in patients with chronic pain is the Multidimensional Pain Inventory (MPl) The MPI is much longer than the simple GCP scale but provides more information for those who find it helpful to have a more detailed measure of psychosocial function. The MPI assesses pain impact (severity and interference), responses of others, and activities and enables patients to be classified into dysfunctional, interpersonally distressed, and adaptive cope subgroups.