Expressed emotion among relatives of chronic pain patients, the interaction between relatives' behaviours and patients' pain experience.

Background: Chronic pain is a sensory and emotional experience that causes significant disturbances to a patient's life as well as to their family. Whether the family environment is affected by chronic pain and, in turn, affects the patients' pain experience has yet to be investigated. The interaction between patients and spouses has been assessed using the expressed emotion (EE) construct, a tool previously described in the field of mental health.