Interventions

The interventions consisted of sending reminders regarding their regular PCP appointments and providing patients with health education aimed at lifestyle modification via a treatment support center that had been established for these purposes beforehand. Reminders for regular medical visits consisted of a letter sent 1 week before the established next visit day (NVD). If this appointment was missed, another letter was sent 2 weeks after the NVD. If required, a telephone call was made to the patient 4 weeks after the NVD. If the patient did not visit the PCP within 6 weeks of the NVD, the PCP or a clinic staff member contacted the patient by either letter or telephone.

Lifestyle modification intervention was provided to encourage progress toward behavioral changes in diet and exercise. Certified diabetes educators, registered dieticians, or public health nurses participating in the standardized program for behavioral theory on patient education provided counseling, which was tailored for each patient according to his or her PCP’s instructions with regard to the target body weight, recommended food intake, and exercise therapy. Patients received six sessions of lifestyle advice through telephone calls, each lasting between 15 and 30 min. Alternatively, some DMAs trained certified diabetes educators and provided them with a location for face-to-face counseling. With these DMAs, there were four face-to-face advice sessions, each lasting approximately 30 min. Furthermore, the PCPs in the intervention group received feedback letters regarding the indicators for themselves as well as the benchmarks for each indicator. All interventions continued for 1 year.