Sources of first and second reports were as follows: 39.0 % Waves 1 and 3; 40.4% Waves 1 and 4; 20.5% Waves 3 and 4. Mean age was 17.3 (SD = 2.1) years at Time 1 and 21.5 (SD = 2.7) years at Time 2. When three reports were available (which was the case for 35.0% of participants with greater than 1 report), the first two were used. This approach (as opposed to conducting analyses with Wave 1 and 4 reports for all participants, for example) allowed us to maintain the largest possible sample size while drawing uniformly on first and second reports. To account for the variation in the pairings of assessments, lag time between reports (mean=4.3 years; SD=1.8) was included as a covariate in analyses.
