User`s guide

Dexcom G4 PLATINUM User’s Guide | 173
Agreement and Accuracy Relative to SMBG
During the study, agreement between the System and blood glucose
values is also characterized using paired System and SMBG results.
The System and SMBG values were compared by pairing the
comparative SMBG value to a System glucose reading that occurred
immediately after the SMBG was collected. These results characterize
the performance subjects expect during real-time use of the System in
their daily diabetes management when comparing the System readings
to their home blood glucose meter results.
Table 11 is categorized within CGM glucose ranges. For readings less
than or equal to 80 mg/dL the absolute difference in mg/dL between
the two glucose results was calculated. For values greater than 80
mg/dL the absolute percent difference (%) from the SMBG values was
calculated. The percentages of total readings within 15 mg/dL or 15%,
20 mg/dL or 20%, 30 mg/dL or 30%, 40 mg/dL or 40% or greater than
40 mg/dL or 40% were then calculated. For example, if the CGM reads
100 mg/dL, it is between 81-180 mg/dL range and you can expect the
CGM readings to be within 20% of the SMBG values 78% of the time for
the Original System and 85% time for the Software 505 System.