Main interventionComparatorNumber of studies
MetforminAny insulin3
MetforminPlacebo or any non-drug intervention21
MetforminMetformin + GLP-1 agonist5
MetforminMetformin + insulin3
ThiazolidinedionePlacebo or any non-drug intervention38
SulfonylureaPlacebo or any non-drug intervention18
DPP-4 inhibitorPlacebo or any non-drug intervention9
MeglitinidesPlacebo or any non-drug intervention10
GLP-1agonistPlacebo or any non-drug intervention1
Metformin + thiazolidinedioneThiazolidinedione + DPP-4inhibitor3
Metformin + thiazolidinedioneThiazolidinedione + GLP-1agonist1
Metformin + thiazolidinedioneSulfonylurea + meglitinides1
Metformin + sulfonylureaThiazolidinedione + basal insulin1
Metformin + sulfonylureaSulfonylurea + basal insulin2
Metformin + GLP-1 agonistThiazolidinedione + GLP-1agonist1
Metformin + GLP-1 agonistSulfonylurea + GLP-1agonist1
Metformin + basal insulinSulfonylurea + basal insulin2
Metformin + premixed insulinSulfonylurea + premixed insulin1
Metformin + premixed insulinMeglitinides + premixed insulin1

From: Appendix E, Tallies for Comparisons Not Included in Review

Cover of Oral Diabetes Medications for Adults With Type 2 Diabetes: An Update
Oral Diabetes Medications for Adults With Type 2 Diabetes: An Update [Internet].
Comparative Effectiveness Reviews, No. 27.
Bennett WL, Wilson LM, Bolen S, et al.

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