Table 3.

Intervention Features of Studies With Significant A1c Outcomes (n = 18).

Review	Intervention features				A1cc
Authora,b	Communication (1- or 2-way)	Patient-generated health data (tracking or analysis)	Education content (general or customized)	Feedback (automated or live)
Garabedian	2	Analysis	Both	Automated	−0.8% decreased
Cui	2	Analysis	Both	Both	−0.4% diff
Alharbi	2	Both	Both	Both	−0.5% diff
Bonotob	2	Both	Both	Both	−0.4% diff P < .001
Greenwood	2	Both	Both	Both	−0.2 to −1.2 rangee
Hou	2	Both	None	Both	−0.5% diff
Kuo	Both	Both	Both	Both	−0.5% diff
Palb	Both	Both	Both	Both	−0.2% diff P = .009 Mobile: −0.5% diff P < .00001
Pereira	Both	Both	Both	Both	Significantf
Saffarib	Both	Both	Both	Both	−0.5% diff P < .001 SMS and Internet: −0.9% diff P < .001
Taob	Both	Both	Both	Both	−0.3% diff P < .00001 Mobile: −0.4% diff. P < .00001
Wu	Both	Both	Both	Both	−0.5% diff T2D: −0. 7% diff
Tomab	Both	Both	General	Both	−0.5% diff P < .00001
Kitsiou	Both	Tracking	General	Both	T2D: 0.8% decreased T1D: −0.3% decreased
Orb	Both	Tracking	General	Both	−0.3% decreased P < .001
Zhaib	Both	Tracking	General	Both	−0.4% diff
Hamine	Both	Tracking	None	Live	11/26 studiesg
Peterson	Both	Tracking	None	None	7/15 studiesg −0.6% to −0.8% rangee

Abbreviations: Diff, difference-between intervention and control; SMS, text messaging; T1D, type 1 diabetes; T2D, type 2 diabetes.

^aAuthors ordered from most features to least features.

^bItems signify a meta-analysis.

^cA1c was not reported consistently in reviews; P values are included if they were reported.

^dDecrease means there was a decrease in A1c reported.

^eRange refers to the range of A1c difference reported.

^fSignificant means authors did not specify an A1c level.

^gStudies indicates the number of studies reporting significant A1C.