OBJECTIVES: Brief Pain Inventory (BPI) is a self-administered questionnaire used to assess severity and impact of pain on daily functions. Developed for use in cancer pain, it is now being widely used in assessment of both malignant and non-malignant pain. To date, no published studies exist summarizing BPI's psychometric properties for both types of pain. The study objective was to examine the existing evidence of the psychometric properties of BPI use in patients suffering from either type of pain. METHODS: A structured literature review was performed to summarize the psychometric properties of the BPI questionnaire in both malignant and non-malignant pain. Published papers and abstracts were retrieved by searching Medline 1983-2006, SciSearch and pain-related websites. Relevant articles cited from these search findings were also reviewed. Key search terms included: Brief Pain Inventory, reliability, responsiveness and validity. Articles were included for critical review if psychometric properties were addressed. RESULTS: Of 202 citations, 22 met inclusion criteria for critical review. Factor analysis was used to establish construct validity, which generated 2-items: intensity and interference. Only one study reported 3-items by separating the interference domain by psychological functions/sleep and physical function. Face and content validity were demonstrated for both types of pain. Studies conducting longitudinal analysis showed BPI scales were sensitive to change and able to discriminate among groups of patients based on condition-specific measures of improvement, no change, or a decline. Intraclass correlation coefficient for test-retest reliability was found to range from 0.61-0.76 for pain intensity and 0.81-0.88 for pain interference in malignant- pain. Internal consistency coefficients were approximately 0.85 for the intensity scale and 0.88 for the interference scale with the Cronbach's alpha coefficients ranging from 0.77-0.95 for non-malignant pain. CONCLUSION: Evidence supports the use of the BPI as a reliable and valid pain assessment tool in malignant and non-malignant pain.