Figure 1.

Mean A1C change from baseline by treatment group. Change equals later A1C minus baseline A1C. This figure shows the raw mean changes and SEMs. A separate multilevel model of the actual A1C values, with a transformation of the time variable to reflect the deceleration of change over time (1/time², with time defined as 1–5), showed that the decline in A1C over the course of the study differed between the groups net of other factors known to cause A1C change: age, sex, diabetes therapy, and initiation of insulin during the study. Specifically, the results of a multilevel model found that the decline for the SMBG group was 0.51% (P = 0.002) and the decline for the RT-CGM group was 1.16% (P < 0.0001). These estimates must be multiplied by 1/time² to obtain the change in A1C, which occurred at each time point.