Table 2 Characteristics of included randomized clinical trials evaluating interventions to improve compliance with lower glycated hemoglobin (HbA1c) in patients with type 1 diabetes according to intervention categories

Psychological category

Ellis, 2005, 2007 [21–24] (4 published complementary reports)

n = 127 Age = 13.3 years Diabetes duration = 5.3 years Male = 62 (48 %) White = 33 (26 %)

Intervention Multisystemic therapy: intensive and home- and community-based, originally designed for youths with antisocial behavior. Duration of intervention: 5.7 months Control Standard medical care: quarterly visit of multidisciplinary team

Intervention Baseline = 11.4 ± 2.2 % End-of-study = 10.8 ± 2.6 % Control Baseline = 11.3 ± 2.3 % End-of-study = 11.3 ± 2.3 % Significant reduction of HbA1c only in the intervention group Compliance evaluation of the psychological intervention: semi structured interview

Nansel, 2007 [25]

n = 81 Age =13.6 years Diabetes duration = 7.6 years Male = 36 (44 %) White = 69 (85 %)

Intervention “Diabetes Personal Trainer”: approach guided by principles of motivational interviewing, applied behavior analysis, and problem solving. Duration of intervention: 2 months Control Education plus standard diabetes care

No significant reduction in HbA1c in intervention and control groups, but absolute values were not described Compliance evaluation of the psychological intervention: modified version of Diabetes –Management Profile

Weinger, 2011 [26]

n = 110^a Age = 46.6 years Diabetes duration = 23.7 years Male = 48 (48 %) White = 105 (96 %)

Intervention Structured behavioral intervention: five 2-hour sessions. Duration of intervention: 6 weeks Control Individual appointments with diabetes nurse and dietitian educators

Intervention Baseline = 9.0 ± 1.9 % End-of-study = 8.7 ± 1.2 % Control Baseline = 8.7 ± 0.6 % End-of-study = 8.5 ± 1.1 % Changes of HbA1c were described but statistical analysis was not reported

Compliance evaluation of the psychological intervention: frequency of diabetes self-care, 3-day pedometer readings, 24-hour diet recalls, average number of glucose checks.

Nansel, 2012 [27]

n = 390 Age = 12.5 years Diabetes duration = 4.8 years Male = 191 (49 %) White = 273 (70 %)

Intervention Clinic-integrated behavioral: designed to improve family diabetes management (WE-CAN manage diabetes). Duration of intervention: 24 months Control Standard medical care

Significant reduction of HbA1c occurred only in the intervention group, but absolute values were not described Compliance evaluation of the psychological intervention: semi structured interview

Mulvaney, 2010 [28]

n = 72 Age =15.1 years Diabetes duration: 6.3 years Male = 40 (56 %) White = 66 (92 %)

Intervention Learning, social-cognitive and self-determination management by website support. Duration of intervention: 11 weeks. Control Usual care

Intervention Baseline = 9.1 ± 1.9 % End-of –study = 9.1 ± 1.8 % Control Baseline = 8.2 ± 1.2 % End-of-study = 8.5 ± 1.3 % No significant reduction in HbA1c in intervention and control groups Compliance evaluation of the psychological intervention: The Diabetes Rating Scale

Franklin, 2006 [29]

n = 61 Age = 13.5 years Diabetes duration = 4.1 years Male = 34 (56 %) White = 59 (97 %) Results referred only to patients on conventional insulin arm

Intervention “Sweet talk”: motivational support network to deliver behavioral intervention through mobile. Duration of intervention: unclear Control Usual care

Intervention Baseline = 9.8 % End-of-study = 10.1 ± 1.7 % Control Baseline = 10.1 % End-of-study = 10.3 ± 1.7 % No significant reduction in HbA1c in intervention and control groups Compliance evaluation of the psychological intervention: self-report adherence

Telecare category

Montori, 2004 [30]

n = 31 Age = 43 years Diabetes duration = 17 years Male = 10 (32 %) White = no information

Intervention Monitoring blood glucose four times/day and transmitting recorded data twice a week with feedback from a nurse supervised by an endocrinologist 24 hours after the transmission. Duration of intervention: 6 months Control Same monitoring requested but without feedback

Intervention Baseline = 9.3 ± 1.3 % End-of-study = 7.8 ± 1.3 % Control Baseline = 8.8 ± 1.2 % End-of-study = 8.2 ± 1.2 % Significant reduction of HbA1c only in the intervention group Compliance evaluation of the telecare intervention: SMBG and insulin use

Lawson, 2005 [31]

n = 46 Age = 15.2 years Diabetes duration = 6.5 years Male = 26 (56 %) White = no information

Intervention Weekly standardized telephone contact with a diabetic nurse specialist to discuss blood sugar over the last week and performing insulin adjustments using standard rules and algorithms. Duration of intervention: 6 months Control Standard care with quarterly visit with a nurse and an endocrinologist

Intervention Baseline = 10 ± 1.3 % End-of-study = 9.4 ± 1.4 % Control Baseline = 9.7 ± 0 .6 % End-of-study = 9.2 ± 1.4 % No significant reduction of HbA1c in intervention and control groups Compliance evaluation of the telecare intervention: general adherence with diabetes management (blood glucose testing, insulin schedule, food plan, glucose goals, exercise)

Farmer, 2005 [32]

n = 93 Age = 23.8 years Diabetes duration = 12.1 years Male = 55 (59 %) White = no information

Intervention Clinical advice and structured specialized nurse counseling in response to real-time blood glucose test results. Duration of intervention: 9 months Control Data transmission without feedback

Intervention Baseline = 9.2 ± 1.1 % End-of-study = 8.6 ± 1.4 % Control Baseline = 9.3 ± 1.5 % End-of-study = 8.9 ± 1.4 % Significant reduction of HbA1c in intervention and control groups, without difference between them Compliance evaluation of the telecare intervention: SMBG

Landau, 2011 [33]

n = 70 Age = 15 years Diabetes duration = 5.7 years Male = 32 (46 %) White = no information

Intervention Weekly upload of the self-monitoring blood glucose and feedback from study coordinator. Parents were contacted if any change in the treatment was necessary. Duration of intervention: 6 months Control Data upload without study coordinator feedback

Intervention Baseline = 8.5 ± 1.4 % End-of-study = 8.5 ± 1.4 Control Baseline = 8.2 ± 1.1 % End-of-study = 8.4 ± 1.1 % No significant reduction of HbA1c in intervention and control groups Compliance evaluation of the telecare intervention: SMBG

Gay, 2006 [34]

n = 100 Age = 13.3 years Diabetes duration = 6.2 years Male = 32 (61 %) White = no information

Intervention Twice a month children went to a selected pharmacy to download data stored in their glucometer. Data was transmitted to a pediatric diabetologist and within 5 days feedback was provided. Duration of intervention: 6 months Control Usual follow-up

Intervention Baseline = 9.2 ± 1.1 % End-of-study = 9.1 ± 1.5 % Control Baseline = 9.2 ± 1 % End-of-study = 9.3 ± 1.2 % No significant reduction of HbA1c in intervention and control groups. There were problems with software installation Compliance evaluation of the telecare intervention: SMBG and insulin adjustments

Esmatjes, 2014 [35]

n = 154 Age = 31.7 years Diabetes duration = 17.7 years Male = 69 (44.9 %) White = no information

Intervention Five telematic visits, and management of the Medical Guard Diabetes (MGD) system (Pulso Ediciones, Barcelona, Spain) with data reports once a month and responses of diabetes team in the following 3 days with recommendations on treatment adjustments. Duration of intervention: 6 months Control All visits were in hospital and data were obtained on site during the visits

Intervention Baseline = 9.3 ± 1.5 % End-of-study = 8.7 ± 1.5 % Control Baseline = 9.2 ± 0.9 % End-of-study = 8.6 ± 0.9 % No significant reduction of HbA1c between intervention and control groups Compliance evaluation of the telecare intervention: self-care treatment adherence

Educational category

Cook, 2002 [36]

n = 53 Age = 14.6 years Diabetes duration = no information Male = 26 (49 %) White = 45 (85 %)

Intervention Small group education to teach adolescents to became more responsible with day-to-day diabetes care (Choices Program). Duration of intervention: 6 weeks Control Usual care

Intervention Baseline = 8.9 ± 1.3 % End-of-study = 8.3 ± 1.4 % Control Baseline = 9.3 ± 2 .1 % End-of-study = 9.0 ± 1.9 % No significant reduction of HbA1c in intervention and control groups at 6 months Compliance evaluation of the educational intervention: SMBG and Diabetes Problem Solving Questionnaire

Howe, 2005 [37]

n = 49 Age = 12.8 years Diabetes duration = no information Male = 28 (57 %) White = 27 (55 %)

Intervention Single educational intervention to provide families with basic diabetes management skills. Duration of intervention: one session Control Standard care with quarterly visit with a nurse practitioner and an endocrinologist

Intervention Baseline = 10.1 ± 1.2 % End-of-study = 9.7 ± 1.9 % Control Baseline = 10.2 ± 1.4 % End-of-study = 9.9 ± 1.6 % No significant reduction of HbA1c in intervention and control groups Compliance evaluation of the educational intervention: Adherence Clinician Checklist

Howe, 2005 [37]

n = 54 Age = 12.1 years Diabetes duration: no information Male = 29 (54 %) White = 28 (52 %)

Intervention Single educational intervention to provide families with basic diabetes management skills plus weekly phone calls for 3 months and then bimonthly. Study coordinator followed a standard protocol on the phone talking about problem-solving skills related to diabetes care. Duration of intervention: 6 months Control Standard care with quarterly visit with nurse practitioner and an endocrinologist

Intervention Baseline = 10 ± 1.4 % End-of-study = 9.5 ± 1.7 % Control Baseline = 10.2 ± 1.4 % End-of-study = 9.9 ± 1.6 % No significant reduction of HbA1c in intervention and control groups Adherence / Compliance evaluation: Adherence Clinician Checklist.

Weinger, 2011 [26]

n = 110^b Age = 46.6 years Diabetes duration = 23.7 years Male = 48 (48 %) White = 105 (96 %)

Intervention Five 2-hour sessions of manual-based group diabetes education Duration of intervention: 6 weeks Control Individual appointments with diabetes nurse and dietitian educators

Results of HbA1c were described together for patients with type 1 and type 2 diabetes Compliance evaluation of the educational intervention: frequency of diabetes self-care, 3-day pedometer readings, 24-hour diet recalls, average number of glucose checks

Nunn, 2006 [38]

n = 123 Age = 11.6 years Diabetes duration = 3.7 years Male = 69 (56 %) White = no information

Intervention Bimonthly phone calls from a diabetes educator covering the three main topics insulin use, carbohydrate intake and blood glucose values with a written educational program. Duration of intervention: 7 months Control Usual care

Intervention Baseline = 8.2 ± 1.1 % End-of-study = 8.9 ± 1.3 % Control Baseline = 8.3 ± 1.01 % End-of-study = 8.8 ± 1.1 % No significant reduction of HbA1c in intervention and control groups at 6 months Compliance evaluation of the educational intervention: SBGM, limited screen time, exercise practice, rotation of injection sites, warrant bracelets worn

Psychoeducation category

Katz, 2014 [39]

n = 153 Diabetes duration = 12.8 years Male = 67 (44 %%) White = no information

Intervention 1 Psychoeducation was performed as 30-minute quarterly sessions with the patient, parent or guardian, and a non-medical care ambassador. Material was related to: family management of diabetes, problem-solving exercises and role-playing realistic expectations, glucose self-monitoring, avoidance of weight gain, and hypoglycemia. Duration of intervention: 2 years Intervention 2 Participants received monthly outreach by the care ambassador via phone or email, in addition to the quarterly diabetes care and ambassador care coordination. Duration of intervention: 2 years Intervention 3 Standard care including basic care coordination by the care ambassador (to assist in scheduling quarterly clinic visits)

Intervention 1 Baseline = 8.3 ± 1.4 % End-of-study = 8.6 ± 1.0 % Intervention 2 Baseline = 8.5 ± 1.4 % End-of-study = 8.8 ± 1.0 % Intervention 3 Baseline = 8.5 ± 1.4 % End-of-study = 8.6 ± 1.0 % No significant reduction of HbA1c in intervention and control groups at 2 years Compliance evaluation of the educational intervention: Diabetes Family Responsibility Questionnaire