Pain and psychological function are initimately linked. Depression is thought to be highly prevalent in patients with chronic pain, and Currie (2004) showed that severity of pain correlated with the rate of major depression. Treatment outcomes in pain management, e.g., spine surgery, have been shown to be predictable by psychological evaluation.

The psychological evaluation consists of a clinical interview, mental status exam, pain screening inventories or pain scales (e.g., visual analog scale, McGill Pain Questionnaire), psychiatric screening or standardized testing, and measures of psychological and behavioral function.

Screening psychiatric testing – examples include the Beck Depression Inventory (BDI) and Symptom Checklist-90-R (SCL-90-R). Many screens, including BDI and SCL-90-R, have high levels of face-validity, meaning that the tests are easily manipulated by patients who seek to misrepresent their emotional state.

The Beck Depression Inventory (Beck and Steer, 1987) is a 21 item, 10 min depression screen. Scores of 0-9 correlate with no depression, whereas score above 30 suggests severe depression. A positive screen requires diagnostic confirmation. The Symptom Checklist-90-R examines psychological symptoms, takes about 15 mins to complete, and is often used on patient intake. Patients screening positively are followed up with a Minnesota Multiphasic Personality Inventory (MMPI-2). SCL-90-R can also be used to monitor progress during treatment.