Self-assessment of patterns of subjective experience: development and psychometric study of the States of Mind Questionnaire

States of mind are forms of subjective experience that involve cognitions, emotions, needs, desires and physical sensations, subjectively, some charged with emotional suffering and some charged with well-being. This study presents a new questionnaire designed of States of Mind Questionnaire (SMQ), focused on the self-assessment of recurring patterns of subjective experience. We first review the literature leading to the development of SMQ and then we investigate its psychometric properties. We conducted an exploratory factor analysis (EFA), internal reliability, inter-correlations between subscales, test-retest reliability, convergent and divergent validity. Finally, we explored the relationship between states of mind and symptoms. The sample was composed of 427 individuals (M age=32; SD=11.49). EFA did not showed a theoretically coherent structure. Internal consistency was good for the 24 subscales (Cronbach’s α of 0.62 to 0.96) and test-retest reliability was adequate. States of mind converged and diverged with maladaptive schemas and predicted symptomatology. Overall results indicate that SMQ may be a valuable tool to help clinicians and patients to assess different and diverse states of mind. However, more research it is required to explore and enhance SMQ psychometric properties in non-clinical clinical groups and in psychotherapy outcomes.