Table 1.

Indices of beta cell function.

Glucose Clamp-Based Indices
Acute insulin response (AIR)	Area under the curve (AUC) of plasma insulin during first 10 min of hyperglycemic clamp (200 mg/dL)
AIRmax	AIR with arginine stimulation
	Reflects maximal insulin secretion
Disposition index (DI)	Insulin secretion (AIR) adjusted for insulin sensitivity (M value)
Indices Based on 75 g Oral Glucose Tolerance Test (OGTT)
Insulinogenic index (II)	Increment of insulin divided by increment of glucose during first 30 min of 75 g OGTT
AUCinsulin/AUCglucose	AUC of insulin divided by AUC of glucose
Oral DI	Homeostasis model assessment of insulin resistance (HOMA-IR) or Matsuda index is used as insulin sensitivity index; i.e., oral DI is calculated as II/HOMA-IR
Indices Based on Single Blood Sample
HOMA-beta	360 × fasting insulin (mU/L)/(fasting glucose (mg/dL) − 63)
C-peptide to glucose ratio (CPRI)	C-peptide (ng/mL)/glucose (mg/dL) (× 100)
	Assessed in fasting and postprandial states