Measurement in pain therapy: is pain relief really the endpoint?

Abstract
Pain is not an isolated symptom. Severe pain creates fatigue, impairs concentration, compromises mood, degrades sleep and diminishes overall activity level. The goal of intervention for chronic pain must include alleviating the functional impairment that pain produces as well as its discomfort. Evaluating treatment outcome requires: (1) quantification of both pain intensity and pain-related impairment; and (2) review of how the relationship between these variables changes as a function of treatment. Simply tracking pain intensity level as an indicator of pain relief is insufficient and can lead to misinterpretation of the effects of an intervention.