Table 3. False Alarm Rates for GW2B Overnight (11 p.m. to 6 a.m.).

Based on the first overnight alarm at a setting of 60 mg/dL.

Alarm Type	Na	Reference Glucose > 60 mg/dLb,c	Reference Glucose > 70 mg/dLb,c
Hypoglycemia Alarm	25	60%	16%
Down Alert Alarm	68	78%	65%
Combinedd	69	77%	62%

^aNumber of GW2Bs giving at least one alarm overnight. Only consider the first alarm for each GW2B.

^bLinearly interpolated value between half-hourly measurements.

^cReference glucose continuously high for ± 30 minutes from time of the alarm.

^dHypoglycemia alarm or the down alert alarm, whichever occurs first.