Skip to main page content
U.S. flag

An official website of the United States government

Dot gov

The .gov means it’s official.
Federal government websites often end in .gov or .mil. Before sharing sensitive information, make sure you’re on a federal government site.

Https

The site is secure.
The https:// ensures that you are connecting to the official website and that any information you provide is encrypted and transmitted securely.

Access keys NCBI Homepage MyNCBI Homepage Main Content Main Navigation
Clinical Trial
. 2010 Jan 1;4(1):41-8.
doi: 10.1177/193229681000400106.

Alarm characterization for continuous glucose monitors used as adjuncts to self-monitoring of blood glucose

Geoffrey McGarraugh  1
Affiliations
Clinical Trial

Alarm characterization for continuous glucose monitors used as adjuncts to self-monitoring of blood glucose

Geoffrey McGarraugh. J Diabetes Sci Technol. .

Abstract

Background: Continuous glucose monitoring (CGM) devices available in the United States are approved for use as adjuncts to self-monitoring of blood glucose (SMBG). Alarm evaluation in the Clinical and Laboratory Standards Institute (CLSI) guideline for CGM does not specifically address devices that employ both CGM and SMBG. In this report, an alarm evaluation method is proposed for these devices.

Method: The proposed method builds on the CLSI method using data from an in-clinic study of subjects with type 1 diabetes. CGM was used to detect glycemic events, and SMBG was used to determine treatment. To optimize detection of a single glucose level, such as 70 mg/dl, a range of alarm threshold settings was evaluated. The alarm characterization provides a choice of alarm settings that trade off detection and false alarms. Detection of a range of high glucose levels was similarly evaluated.

Results: Using low glucose alarms, detection of 70 mg/dl within 30 minutes increased from 64 to 97% as alarm settings increased from 70 to 100 mg/dl, and alarms that did not require treatment (SMBG >85 mg/dl) increased from 18 to 52%. Using high glucose alarms, detection of 180 mg/dl within 30 minutes increased from 87 to 96% as alarm settings decreased from 180 to 165 mg/dl, and alarms that did not require treatment (SMBG <180 mg/dl) increased from 24 to 42%.

Conclusion: The proposed alarm evaluation method provides information for choosing appropriate alarm thresholds and reflects the clinical utility of CGM alarms.

PubMed Disclaimer

Figures

Figure 1.
Figure 1.
Failure to detect a hypoglycemic event by CLSI evaluation.
Figure 2.
Figure 2.
Hypoglycemic false alarm by CLSI evaluation.
Figure 3.
Figure 3.
Hypoglycemic event detected with a false alarm.
See this image and copyright information in PMC

Similar articles

See all similar articles

Cited by

See all "Cited by" articles

References

    1. Pitzer KR, Desai S, Dunn T, Edelman S, Jayalakshmi Y, Kennedy J, Tamada JA, Potts RO. Detection of hypoglycemia with the GlucoWatch Biographer. Diabetes Care. 2001;24(5):803–804. - PubMed
    1. Clinical and Laboratory Standards Institute. Performance metrics for continuous interstitial glucose monitoring; approved guideline. 2008. POCT05-A (28)33.
    1. Buckingham B, Block J, Burdick J, Kalajian A, Kollman C, Choy M, Wilson DM, Chase P. Diabetes Research in Children Network. Response to nocturnal alarms using a real-time glucose sensor. Diabetes Technol Ther. 2005;7(3):440–447. - PMC - PubMed
    1. International Standards Organization. In vitro diagnostic test systems: requirements for blood-glucose monitoring systems for self-testing in managing diabetes mellitus. 2003. ISO 15197:2003(E)
    1. Weinstein RL, Schwartz SL, Brazg RL, Bugler JR, Peyser TA, McGarraugh GV. Accuracy of the 5-day FreeStyle Navigator Continuous Glucose Monitoring System: comparison with frequent laboratory reference measurements. Diabetes Care. 2007;30(5):1125–1130. - PubMed

Publication types

MeSH terms