Predicting anxiety and depression from personality: Is there a synergistic effect of neuroticism and extraversion?

In a longitudinal study of college students, B. S. Gershuny and K. J. Sher (1998) found that high neuroticism and low extraversion had a synergistic effect in predicting anxiety and depression 3 years later. This article attempted to replicate their finding using data from 2 community samples: (a) a cross-sectional survey of 2,677 persons aged 18-79 years, and (b) a longitudinal study in which 441 persons aged 70 or older were followed over 3-4 years. Both studies found that neuroticism predicted anxiety and depression, but there were no Neuroticism X Extraversion interaction effects. These results cast doubt on the generalizability of the original findings.