Analyses

Descriptive statistics were calculated to characterize the sample for youths' demographic and adherence data and HbA1c. Simple correlations examined the bivariate association between each of the insulin scores and youths' HbA1c levels. We also examined bivariate correlations between youths' HbA1c levels and their age, gender, and race (dichotomized white vs. not white because of sample limitations). Finally, a series of exploratory and stepwise multiple regressions were used to determine if the alternate scoring procedures of youths' insulin bolusing behavior (e.g., 2h-BOLUS, TOTAL-BOLUS, BOLUS × %Total Corrections, BOLUS × %Meal Corrections) were superior to the original BOLUS scoring in predicting youths' HbA1c levels. In these regression models, the additional covariates of age, gender, SMBG, and race were included when significant. Steiger's Z test was used in the R statistical package (R Foundation for Statistical Computing, Vienna, Austria)⁷ to evaluate the difference in correlations between HbA1c and BOLUS, 2h-BOLUS, and TOTAL-BOLUS, respectively.