Validation of the Beck Motivation Inventory in a Schizophrenia Sample

Abstract

Objectives: Low motivation is an obstacle to recovery for many individuals with schizophrenia, and assessing motivation remains challenging. The aim of this study was to examine the reliability and validity of a new measure of motivation, The Beck Motivation Inventory (BMI). The BMI is a 13-item measure created to assess self-reported behavior related to an individual’s ability to initiate and sustain task-related motivation, as opposed to relying on others to encourage task-related motivation. Methods: In a sample of 251 adult outpatients and inpatients with schizophrenia or schizoaffective disorder, the BMI was administered along with measures of social functioning and dependent and autonomy beliefs. A confirmatory factor analysis was conducted to test a two-factor model, which consisted of an inner- and other- directed motivation factor. The BMI’s internal consistency, test-retest reliability, and convergent and predictive validity were also assessed. Results: The BMI demonstrated acceptable internal consistency (α > .70) and adequate test-retest stability after six months (r > .5). Convergent validity was established with measures of dependent and autonomy beliefs, and predictive validity was demonstrated with a measure of social functioning. The two-factor model of the BMI was also supported. Conclusions: Results provide initial support for the validation of the BMI, suggesting that the BMI may be a useful and brief tool for evaluating behaviors linked to task-related motivation that may act as obstacles to recovery for individuals with schizophrenia.