at ~17 years of age), then decreased again into young adulthood, though never dipping below early adolescent levels. (βintercept = 16.86, p < .001; βlinear = 1.97, p < .001; βquadratic = −.19, p < .001); that is, a stable high externalizing pattern. Post-hoc analyses suggested a difference in the distribution of trajectory class membership across the sexes (χ2, 2 = 8.49, p = .014) which corresponded to higher posterior probabilities of membership in the decreasing low externalizing class among females (t, 440.79 = −2.795, p = .005).
