OBJECTIVES: To establish the concurrent and discriminatory validity, and relative item importance of the previously developed client-centered, 51-item Schizophrenia Outcomes Assessment Project (SOAP-51) survey, a self-administered, health-related quality of life instrument for individuals with schizophrenia living in the community. METHOD: We asked 1500 community-based clients with schizophrenia, and 150 of their caregivers (using the shortened objective version), in five ethnically and geographically diverse areas within the US to complete the SOAP-51 four times over a three-month period; client retention was 84.2%. Average age was 42.8 years, 60% males. For concurrent validation, clients rated the impact of their condition on each of SOAP-51's eight factors; this was compared to their factor score. For discriminate validity, the caregivers assigned clients to one of four quartiles describing their perception of the client's ability to objectively function in each factor area. Client factor scores were compared to caregiver-reported functional levels. An additional 300 clients rated the relative importance of each item. RESULTS: Cronbach's alpha for the eight factors was 0.71-0.88, test-retest reliability, 0.78-0.99. Client factor scores lowered as clients felt the condition had more negatively impacted on their lives (p < .001). Client factor scores improved with improving caregiver-perceived assessment of client functionality (p < .001). Client scores from the lowest to highest assigned quartile had average scores of 42.7%, 49.3%, 54.7%, and 60.0%, respectively. Ninety two percent of both clients and caregivers considered the survey valuable for monitoring client progress. No significant difference (p > .05) was observed in importance weights for the eight factors, or 51 items, age or gender of client, caregiver or client responses. CONCLUSIONS: Concurrent and discriminatory validity show that the SOAP-51 meets psychometric characteristics for use as a client-centered outcomes measure in patient monitoring and management, and health policy decision-making.