Wave 4. We implemented this difference-indifference approach by creating model constraint parameters in MPLUS that estimated the difference in estimates of effect across waves, and tested whether these parameters were significantly different from 0 (0 would indicate no difference in the estimates of effect across wave) (Muthen & Muthen, (1998-2012)). Models were estimated first unadjusted and then adjusted for age within wave, highest level of parental education, urban versus rural location, family use of public assistance, and household income. Complex sampling weights were included in all stages of analysis. SAS version 9.4 was used for data management, and MPLUS version 7 was used for all analysis.
