Tables 1, 2 and 3 present correlations among all the measures (indicators) used in this model. A missing value analysis was conducted using the PASW (SPSS) software version 18.0.2. The Little’s MCAR test conducted on all measures (excluding categorical variables, i.e., gender, ethnicity, and treatment group) revealed that the pattern of missing values was not completely random, χ2(577) = 756.91, p<0.001. We thus conducted further analyses to understand the missing data patterns by creating a measure of missing data representing the number of indicators used in the model for which we had no valid data (an occasional failure from any informant to answer one question within a scale was not counted as missing data, because average scale scores were computed). A lower score on all three effortful control measures (self, parent, and teacher reports) predicted a higher number of missing values, which is not surprising because a certain level of effortful control is necessary for students to be able to persevere through the task of completing all measures, year after year. Also, a higher number of missing values was related
