Measuring child and adolescent emotional lability: How do questionnaire‐based ratings relate to experienced and observed emotion in everyday life and experimental settings?

Objectives Emotional lability (EL) is an important trans-diagnostic concept that is associated with significant functional impairment in childhood and adolescence. EL is typically measured with questionnaires, although little is known about the ecological validity of these ratings. In this paper, we undertook 2 studies addressing this issue by examining the relationship between rating-based measures of EL and directly measured emotional expressions and experiences. Furthermore, the associations between directly measured emotional expressions and experiences and attention-deficit/hyperactivity disorder (ADHD) symptomatology were also examined, given the clear association of EL with ADHD in former research. Methods In Study 1, we examined the relationship between parental report of children's EL and ADHD, and children's emotional expressions in an experimental context (N = 67). In Study 2, we examined the relationship between parental ratings and real-time measures of emotional experiences in daily life in adolescents (N = 65). Results EL ratings were associated with different elements of real-time emotional experiences and expressions. Elements of emotional expressions but not emotional experiences were also associated with ADHD symptom reports. Conclusions These studies provide evidence for the ecological validity of EL ratings. Furthermore, they add evidence for the associations between EL and ADHD.