Screening tool identifies high-risk drivers with type 1 diabetes and website helps to avoid future accidents

Significant independent predictors of risk for driving mishaps included annual driving distance and presence of peripheral neuropathy. Researchers developed an 11-item questionnaire to further refine risk prediction.


Researchers recently validated a questionnaire to detect drivers with type 1 diabetes who are at high risk for driving mishaps and found that an online hypoglycemia education tool helped them avoid future mishaps.

Driving mishaps were defined as collisions, moving vehicle violations, episodes of severe hypoglycemia while driving, loss of vehicle control, arriving at a destination with no awareness of the drive, and instances of impaired driving in which another person took over driving.

Using factors associated with higher risk of mishaps, researchers developed the screening questionnaire, the Risk Assessment of Diabetic Drivers (RADD). In a separate study, they validated the RADD and tested the effects of an educational intervention, DiabetesDriving.com. The online tool was created to help high-risk drivers better anticipate, prevent, detect, and treat hypoglycemia while driving. Results were published online on April 27 by Diabetes Care.

To develop the 11-item RADD questionnaire (which will soon be available on the American Diabetes Association's website), researchers followed 371 drivers with type 1 diabetes (mean age, 42.5; 48% male) over the course of one year. Participants reported their driving mishaps using monthly diaries.

Over 12 months of follow-up, participants reported an average of 1.77 ± 3.26 yearly driving mishaps each, with 8.4% of drivers reporting six or more driving mishaps. Significant independent predictors of risk for future driving mishaps included annual driving distance and presence of peripheral neuropathy, and the equation used to calculate RADD score took these factors into account.

Drivers were classified as low risk if they had one or fewer mishaps, whereas drivers who had more than one mishap were classified as high risk. The RADD model had 61% sensitivity (correct classification as high risk) and 75% specificity (correct classification as low risk) and categorized 37.5% of participants as high risk (mean, 3.03 ± 4.39 mishaps over 12 months).

In the validation and intervention study, 375 high-risk participants were randomized to receive routine care/no online intervention (n=122), the online education tool (n=124), or the online tool plus motivational interviewing (n=129). Participants were compared with 118 low-risk participants who received routine care.

The intervention groups had 70 days to complete the intervention, after which all participants completed posttreatment assessment questionnaires and 12 monthly driving diaries. The combined intervention group showed no significant differences from the website-only group in completion rates, number of mishaps, or other outcome variables, so the two were combined into a single intervention group.

The intervention group reported fewer mishaps than high-risk participants who received routine care (P=0.01) but more than the low-risk group receiving routine care (P=0.026). The online intervention reduced the difference in mishaps between the high-risk and low-risk groups receiving routine care by 63%.

The study authors clarified that the online intervention only affected hypoglycemia-related driving mishaps, not events related to hyperglycemia or unrelated to diabetes. They noted limitations of the studies, including their reliance on self-report and the inability to determine if a simpler intervention would have been as effective as the five-component intervention.