Table 2.

Summary of intervention, patient, and outcome characteristics

Author year	Participants	Intervention and control	Outcome measures	Significant findings
Gordon 2020 [20] USA	87 T2D rural living veterans, HbA1c 8.5%	12-min video and pamphlet designed to improve provider-patient communication during video consultation Fully digital solution One off session Control: Pamphlet version of provider-patient communication support	Ratings for post-visit provider-patient therapeutic alliance	Patients who watched a pre-visit educational video before their telehealth video consultation reported higher therapeutic alliance scores post-visit than the control group
Gunawardena 2019 [27] Sri Lanka	67 T2D patients Mean age 52 years, 40% female, HbA1c 9.4%	Mobile app designed to support glucose management Fully digital solution 6 months Control: Usual care	App usage HbA1c	Significantly lower A1c levels compared to the control group were observed over 6 months A1c improvement was positively correlated with app usage with over 80% using the app 8–9 times/week and 52% 12 times or more/week and 78% at 6 months
Kerfoot 2017 [19] USA	456 T2D veterans, Mean age 60 years, 6.% female, HbA1c 9.0%	Online diabetes self-management game with integrated teams competition Integrated solution 6 months Control: non-diabetes related game	HbA1c	The intervention group had significantly greater reductions in mean HbA1c over 6 months compared to the control
Kusnanto 2019 [26] Indonesia	65 T2D patient 57% female, HbA1c 8.5%	Diabetes calendar app for SM education program Fully digital solution 3 months Control: Leaflet version of SM education program	Diabetes management self-efficacy scale (DMSES) HbA1c Cholesterol, triglyceride, LDL-c, insulin level	The intervention group had a significantly higher self-efficacy scores than the control group The intervention group had a significantly lower mean HbA1c levels than the control group The intervention group had a significantly better cholesterol, triglyceride, LDL-c, and insulin levels than the control group
Poppe 2019 [23] Belgium	54 T2D patients Mean age 63 years, 27% female	Website and app designed to increase physical activity and reduce sedentary behavior Fully digital solution 5 weeks Control: Wait-list control	Accelerometer assessed breaks from sedentary time	The intervention group displayed a significant increase in accelerometer-assessed breaks from sedentary time in comparison with the control group
Capozza 2015 [18] USA	93 T2D patients Mean age 53 years 61% female	Two-way SMS system designed to improve glycemic control through coaching, education and testing reminders Fully digital solution 180 days Control: Usual care	CSQ-8 (8-question Client Satisfaction Questionniare) Satisfaction survey Frequency of engagement HbA1c	Mean satisfaction score was 27.7/32 at 180 days 85% said “yes” to having improved disease knowledge and management strategies 94% said "yes” they would recommend intervention others 29% demonstrated frequent engagement (texting responses at least 3 × per week for ≥ 90 days) Both groups had decreased HbA1c but there was no significant difference between them
Hilmarsdottir 2020 [25] Iceland	37 T2D patients Mean age 51yrs, 63% female, HbA1c 7.8%	Gamified app designed to support healthy lifestyle behaviors with the option to compete with other users Integrated solution 6 months Control: Usual care	Problem Areas in Diabetes Scale (PAID) Satisfaction survey Hospital Anxiety and Depression Scale (HADS) HbA1c	There was a significant decrease in the intervention group (but not between groups) in diabetes distress anxiety symptoms and HbA1c levels
Lee 2020 [22] South Korea	72 T2D patients Mean age 50 years, 68% female, HbA1c 7.4%	Diabetes self-management education app with individualized feedback from health care professionals via the app Integrated solution 6 months Control: Usual care	Diabetes Treatment Satisfaction Questionnaire (DTSQc) HbA1c	The intervention group had a significantly higher rates of treatment satisfaction than the control group
Whittemore 2019 [29] Mexico	47 T2D patients Mean age 56 years, 68% female	Diabetes self-management group sessions (in-person) followed by a texting system to support behavior change Integrated solution 7.6 months Control: Usual care	Diabetes self-efficacy Blood glucose monitoring HbA1c	In the intervention group, HbA1c score, diet, and exercise was significantly improved (but not in comparison to the control)
Xu 2020 [21] USA	65 low-income, mostly African American T2D patients Mean age 55 years, 68% female, HbA1c 9.5%	SMS/phone system designed to improve reduce HbA1c and fasting blood glucose (FBG) self-management through automated contact and some bidirectional communication Integrated solution 6 months Control: Reduced version of digital intervention (i.e., weekly only SMS and no bidirectional communication)	Engagement as measured by proportion responding to ≥ 25% of texts or calls over 4 weeks Fasting blood glucose HbA1c	Engagement was 58% for the intervention group and 48% for the control group The intervention groups had significantly decreased HbA1c and self-reported fasting blood glucose while the control group did not