It is believed by many researchers that little attention has been given to patients' perceptions of the impact of chronic pain on their lives. In recognition of this need, G. Frank Lawlis, C. Edward McCoy, and David K. Selby developed the Dallas Pain Questionnaire (DPQ) to assess the amount of chronic pain that affects four aspects (daily activities, work-leisure activities, anxiety-depression, and social interest) of the patients' lives. The present study, conducted to validate the DPQ's statistical properties, first reviews the literature addressing the various theories and varieties of pain, its opiates, and the two current approaches to quantify pain. This study included a total of 143 subjects. Clinical subjects were 104 inpatients in the Spinal and Chronic Pain Center at Medical Arts Hospital and 15 chronic pain outpatients released to work. Normal subjects consisted of staffing personnel (n = 13) and flight assistance employees (U = 11)- Both clinical and normal groups completed the DPQ. The Minnesota Multiphasic Personality Inventory (MMPI) was administered only to the clinical population. Results suggest that the DPQ is both externally reliable (stability reliability coefficient of .970) as well as an internally consistent instrument. Two factors emerged from factor structure analysis. Factor one (63.2% …