Final answer:
The meta-analysis of personality using the Big Five framework indicates that personality traits such as conscientiousness and agreeableness generally increase with age, while neuroticism and extraversion slightly decline, with significant personality trait changes occurring during early adulthood.
Step-by-step explanation:
The general conclusion of the meta-analysis of personality stability and change, organized according to the Big-Five framework that included 87 longitudinal studies, suggests that personality traits exhibit both stability and change across the lifespan. Research within the framework of the Big Five personality factors—openness, conscientiousness, extraversion, agreeableness, and neuroticism—indicates that certain traits such as conscientiousness and agreeableness tend to increase with age, particularly from young adulthood into middle age and then peaking between ages 50 and 70, respectively. On the other hand, neuroticism and extraversion show a slight decline with age. Specifically, conscientiousness increases as individuals manage their personal relationships and careers more effectively, while agreeableness increases as individuals become more cooperative and compassionate as they age. The meta-analysis highlights that personality traits changed most during early adulthood.