Principles & Practice of Pain Medicine > Part II. Pain: General Principles and Evaluation > Chapter 7. Outcome Measurements in Pain Medicine Harriët Wittink, Leonidas C. Goudas, Scott Strassels, and Daniel B. Carr

Pain-Specific Outcomes Measurement

"Pain, in general, and chronic and persistent pain, specifically, is a unique challenge to outcomes research because of the importance of subjective information. Unlike the majority of other medical conditions, chronic pain may not involve a distinct organ system, pathophysiologic process, or specific discipline. Although pain is characterized as a symptom, it is, in fact, a subjective experience, a perception.⁴¹ This perception not only depends on nociceptive transmission and modulation within the CNS, but is integrated with psychological, social, and other environmental factors.⁴² Physical functioning, work, family, and social relationships are usually impaired by chronic pain. Comorbid conditions, such as depression or anxiety, often accompany chronic pain.⁴³ For these reasons, it is argued that the assessment of patients with chronic pain should be accomplished within a multidimensional framework.⁴⁴ Assessment of chronic pain should provide clinicians with relevant information to formulate a treatment plan, and also allow for measurement of the outcome of treatment interventions. The generic HRQOL instruments discussed earlier are mostly epidemiologic tools and as such are able to measure change in large samples of patients. By design they are not intended, nor are they sufficiently sensitive, to measure changes in a single subject. Furthermore, these instruments do not provide information on items frequently assessed in pain management, such as solicitous responses,^45,46 coping ability,^47,48..."