Externalizing problems showed convergent validity across time from block 1 to block 2 (r = .65, p < .001) and from block 2 to block 3 (r = .62, p < .001). Although externalizing problems predicted later internalizing problems from block 1 to block 2 (r = .32, p < .001) and from block 2 to block 3 (r = .37, p < .001), the associations were stronger from externalizing problems to later externalizing problems than to later internalizing problems from block 1 to 2 (Fisher’s r-to-z = 7.00, p < .001) and from block 2 to 3 (z = 5.04, p < .001). Thus, there was cross-time convergent and discriminant validity for externalizing and internalizing problems across all three blocks.
