Validating measures of real-world outcome: the results of the VALERO expert survey and RAND panel

Abstract

Background: People with schizophrenia demonstrate considerable discrepancy between self-reported functioning and informant reports. It is not clear whether these discrepancies originate from the instruments used or from the perspectives of different informants. The goal of the Validation of Everyday Real-World Outcomes (VALERO) Study is to enhance the measurement of real-world (RW) outcomes in the social, residential, and vocational domains through selection of optimal scales and informants using a multistep process similar to the Measurement and Treatment Research to Improve Cognition in Schizophrenia (MATRICS) initiative.

Methods: Forty-eight experts provided their opinion regarding the best scales measuring RW outcomes. Fifty-nine measures were nominated. The investigators selected the 11 scales that were the most highly nominated, had the most published validity data, and best represented the domains of interest. Information was provided to other experts who served as RAND panelists. Panelists rated each measure for its suitability across multiple a priori domains. Discrepant ratings were discussed until consensus was reached.

Results: Following the RAND Panel, the 2 scales that scored highest across the various criteria for each of the classes of scales (hybrid, social functioning, and everyday living skills) were selected for use in the first substudy of VALERO. The scales selected were the Quality-of-Life Scale, Specific Levels of Functioning Scale, Social Behavior Schedule, Social Functioning Scale, Independent Living Skills Schedule, and Life Skills Profile.

Discussion: The results show that although there are significant limitations with current scales used for the assessment of RW outcome in schizophrenia, a consensus is possible. Further, several existing instruments were rated as useful for measuring social, residential, and vocational outcomes.