Factors that affect functional status in patients with cancer-related pain.

Cancer-related pain in outpatient adult populations remains high and has a direct effect on functional status. Factors that affect functional status have been explored separately, but the inter-relatedness of those factors has not been examined. Using a cross-sectional design, the purpose of this study was to examine the relationships between pain level, beliefs about pain, symptom distress, perceived control over pain, and functional status in 304 ambulatory cancer patients who experienced cancer-related pain within the past 2 weeks. Participants completed standardized questionnaires during regularly scheduled clinic visits. Patient's pain level was positively related to increased distress and decreased perceived control over pain and functional status. Structural equation modeling indicated that symptom distress mediated the relation between pain level and functional status. Perceived control over pain had a direct effect on symptom distress and mediated the effect of beliefs about pain and pain level on symptom distress. Patients' perceived control over pain may be an important component in pain management. The direct and mediating effects of perceived control and symptom distress suggest areas of further research. Interventions to increase knowledge and decrease barriers to pain control have the potential for increasing perceived control over pain.