Measuring Positive Emotion With the Mood and Anxiety Symptom Questionnaire: Psychometric Properties of the Anhedonic Depression Scale.

Low positive emotion distinguishes depression from most types of anxiety. Formative work in this area employed the Anhedonic Depression scale from the Mood and Anxiety Symptom Questionnaire (MASQ-AD), and the MASQ-AD has since become a popular measure of positive emotion, often used independently of the full MASQ. However, two key assumptions about the MASQ-AD-that it should be represented by a total scale score, and that it measures time-variant experiences-have not been adequately tested. The present study factor analyzed MASQ-AD data collected annually over 3 years (n = 618, mean age = 17 years at baseline), and then decomposed its stable and unstable components. The results suggested the data were best represented by a hierarchical structure, and that less than one quarter of the variance in the general factor fluctuated over time. The implications for interpreting past findings from the MASQ-AD, and for conducting future research with the scale, are discussed.