The Diabetes Technology Society Error Grid and Trend Accuracy Matrix for Glucose Monitors.
Klonoff DC., Freckmann G., Pleus S., Kovatchev BP., Kerr D., Tse CC., Li C., Agus MSD., Dungan K., Voglová Hagerf B., Krouwer JS., Lee W-AA., Misra S., Rhee SY., Sabharwal A., Seley JJ., Shah VN., Tran NK., Waki K., Worth C., Tian T., Aaron RE., Rutledge K., Ho CN., Ayers AT., Adler A., Ahn DT., Aktürk HK., Al-Sofiani ME., Bailey TS., Baker M., Bally L., Bannuru RR., Bauer EM., Bee YM., Blanchette JE., Cengiz E., Chase JG., Y Chen K., Cherñavvsky D., Clements M., Cote GL., Dhatariya KK., Drincic A., Ejskjaer N., Espinoza J., Fabris C., Fleming GA., Gabbay MAL., Galindo RJ., Gómez-Medina AM., Heinemann L., Hermanns N., Hoang T., Hussain S., Jacobs PG., Jendle J., Joshi SR., Koliwad SK., Lal RA., Leiter LA., Lind M., Mader JK., Maran A., Masharani U., Mathioudakis N., McShane M., Mehta C., Moon S-J., Nichols JH., O'Neal DN., Pasquel FJ., Peters AL., Pfützner A., Pop-Busui R., Ranjitkar P., Rhee CM., Sacks DB., Schmidt S., Schwaighofer SM., Sheng B., Simonson GD., Sode K., Spanakis EK., Spartano NL., Umpierrez GE., Vareth M., Vesper HW., Wang J., Wright E., Wu AHB., Yeshiwas S., Zilbermint M., Kohn MA.
INTRODUCTION: An error grid compares measured versus reference glucose concentrations to assign clinical risk values to observed errors. Widely used error grids for blood glucose monitors (BGMs) have limited value because they do not also reflect clinical accuracy of continuous glucose monitors (CGMs). METHODS: Diabetes Technology Society (DTS) convened 89 international experts in glucose monitoring to (1) smooth the borders of the Surveillance Error Grid (SEG) zones and create a user-friendly tool-the DTS Error Grid; (2) define five risk zones of clinical point accuracy (A-E) to be identical for BGMs and CGMs; (3) determine a relationship between DTS Error Grid percent in Zone A and mean absolute relative difference (MARD) from analyzing 22 BGM and nine CGM accuracy studies; and (4) create trend risk categories (1-5) for CGM trend accuracy. RESULTS: The DTS Error Grid for point accuracy contains five risk zones (A-E) with straight-line borders that can be applied to both BGM and CGM accuracy data. In a data set combining point accuracy data from 18 BGMs, 2.6% of total data pairs equally moved from Zones A to B and vice versa (SEG compared with DTS Error Grid). For every 1% increase in percent data in Zone A, the MARD decreased by approximately 0.33%. We also created a DTS Trend Accuracy Matrix with five trend risk categories (1-5) for CGM-reported trend indicators compared with reference trends calculated from reference glucose. CONCLUSION: The DTS Error Grid combines contemporary clinician input regarding clinical point accuracy for BGMs and CGMs. The DTS Trend Accuracy Matrix assesses accuracy of CGM trend indicators.