Resumen de The stability of adult personality varies across age: : Evidence from a two-year longitudinal sample of adult New Zealanders

Petar Milojev, Chris G. Sibley

• We model developmental patterns in the stability of Big-Six personality markers over a two-year period in a multi-cohort panel study of adult New Zealanders (n = 3910). Structural Equation Models testing patterns of linear, quadratic and cubic effects identified considerable variation in the stability of most aspects of personality across the adult age range (20�80 years). Agreeableness showed a slight linear decrease in consistency with increasing age. Extraversion, Conscientiousness, Neuroticism, Openness to Experience, and Honesty�Humility exhibited quadratic �inverted U� patterns of rank-order stability. Unlike Agreeableness, the two-year consistency of these other personality dimensions increased from young adulthood towards middle age, then decreased as people progressed toward old age. Implications for personality research and emerging trends are discussed.