Much emphasis has been placed on specific developmental transitions in personality maturation, the most famous being that personality stability is achieved at age 30 (McCrae & Costa, 1994; cf. Srivastava, John, Gosling, & Potter, 2003). However, there have also been accounts that continuous, progressive trends may better represent personality development. For example, Caspi and colleagues (2005) noted that “the level of stability increases in a relatively linear [read continuous] fashion through adolescence and young adulthood” (p. 467). Importantly, because differential stability is inherently a population-level statistic that indexes the ordering of individuals relative to one another, between-person heterogeneities in the timing and rate of life transition can result in smoothed population-level age trend in differential stability in spite of discontinuities in individual-level developmental trajectories. For the current meta-analysis we will provide results of two analytic approaches: a linear spline approach, where turning points are selected on a priori grounds on the basis of typical transitions previously identified as meaningful in the literature, and a continuous parametric approach which represents development more progressively. In the current context, the spline and continuous
