Twenty-six studies (over 4,811 participants) were included in the review: 14 RCTs, 3 controlled clinical trials (CCTs), 4 pre-test post-test studies and 5 post-intervention only studies.
A non-statistically significant decline was reported in the only study assessing HbA1c in the internet-assisted education group.
Two of the 4 studies in the telephone-automated calls intervention category that assessed HbA1c found a statistically significant decrease in levels (p<0.05). One CCT (n=204) found a large decrease (p<0.05) and one pre-test post-test study (n=184) found a moderate decrease (p<0.05) in HbA1c levels. The remaining studies (2 RCTs, n=520) found small to moderate decreases in HbA1c, but these were not statistically significant.
In studies assessing telemedicine, one RCT (n=28) found a large statistically significant (p<0.05) decrease in HbA1c levels. A second RCT (n=46) found a moderate decrease, but this was not statistically significant.
Six of the 8 studies assessing HbA1c in the CAL group found a decline in levels, although this was only statistically significant (p<0.05) in 3 studies (2 RCTs and 1 CCT, n=1,164).
There were no statistically significant differences between treatment groups in the study assessing HbA1c for an electronic disease management system.
No studies assessing either a personal database manager or computer-assisted flowsheets reported assessing HbA1c levels. Generally no statistically significant differences between intervention and control groups were found in studies assessing change in body weight, blood-pressure, microalbumin or creatinine levels (data not reported). Studies assessing lipids and depression found significant and non significant decreases (data not reported).
Health care utilisation.
Eight studies evaluated health care utilisation. In the group of studies assessing automated calls, there were no changes reported in terms of hospitalisations (1 RCT, n=248) and no change in the number of eye examinations (1 RCT, n=272). Mixed results were reported in terms of primary care visits (4 studies, n=908) and the number of foot examinations (2 RCTs, n=520). However, none of the changes were reported to be statistically significant.
In studies assessing CAL, mixed results were found for number of eye examinations (2 studies, n=728) and for the number of HbA1c tests (3 studies, n=928). One study (n=169) assessing the use of a personal database manager found a decline for number of hospitalisations and primary care visits, but these differences were not reported to be statistically significant.