Global Self-Rated Mental Health: Associations With Other Mental Health Measures and With Role Functioning

Abstract
Background: A large body of research shows that global self-rated health is related to important outcome variables. Increasingly, studies also obtain a single global self-rating of mental health, but understanding of what this item measures is limited. Objective: To clarify interpretation of self-reported mental health, we examine its associations with other validated measures of mental health and role functioning. Research Design: We conducted cross-sectional analyses of nationally representative data from the Medical Expenditure Panel Survey. Measures: In-person household interviews obtained data on global self-reported mental health and any limitations in work, school, or housekeeping activities. Adult respondents (N = 11,109) completed the SF-12 health status survey, the K6 scale of nonspecific psychologic distress, and the Patient Health Questionnaire (PHQ-2) depression screener in a self-administered questionnaire. We used the SF-12 Mental Component Summary and the mental health subscale. Analyses examined associations among mental health measures and regressed activity limitations, and the SF-12 physical and emotional role functioning scales on mental health measures, controlling for demographics and selected chronic conditions. Results: The 4 multi-item mental health measures were strongly correlated with each other (r > 0.69), but correlated less strongly with the self-reported mental health item (r ≈ 0.4). In an exploratory factor analysis, self-reported mental health loaded on both mental and physical health factors. In multivariate analyses, each mental health variable was significantly associated with activity limitations and with role functioning, but the association of self-reported mental health with emotional role functioning was relatively weak. Conclusions: Although global self-rated mental health is related to symptoms of psychologic distress, it cannot be considered to be a substitute for them.