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Multifaceted intervention to promote the regular visiting of patients with diabetes to primary care physicians: rationale, design and conduct of a cluster-randomized controlled trial. The Japan Diabetes Outcome Intervention Trial-2 study protocol



Regular clinic visits are essential for keeping diabetes well controlled. Nevertheless, about half of the known diabetic patients do not receive regular medical care, as estimated by the National Survey in Japan. From the viewpoint of medical resources, primary care physicians (PCPs) should provide regular medical care to the many diabetic patients in Japan. Therefore, maintaining regular care and improving care quality are expected for diabetes treatment at the PCP level.


The Japan Diabetes Outcome Intervention Trial-2 (J-DOIT2) is a cluster-randomized two-armed intervention study. Fifteen district medical associations (DMAs) and 300 PCPs will participate. The PCPs in each DMA will be divided into two groups and randomized, with each group acting as a cluster within the DMA. Then, 3,750 type 2 diabetes patients (aged 40–64 years) will be recruited. In the intervention group, patients will receive reminders for medical visits to their PCP and lifestyle advice over the telephone or face to face. The PCPs will be provided with benchmark indicators of his/her own diabetes treatment activities. In the control group, the PCPs will provide ordinary medical treatment to his/her patients. With a 1-year intervention and follow-up period, the primary outcome will be the rate of patient dropout from regular medical care of both groups. The quality of diabetes treatment provided by the PCPs will also be evaluated.


The J-DOIT2 is a large-scale trial for improvement of diabetes care in an ordinary primary care setting and is expected to contribute to establishing widely adoptable countermeasures for diabetes.

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Fig. 1



Control group


Clinical research coordinator


District medical association


Intervention group


Japan Diabetes Outcome Intervention Trial


J-DOIT2 large-scale trial


J-DOIT2 pilot study


Lifestyle adviser


Next visit day


Primary care physician


Treatment support center


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This study is funded by a Health and Labour Sciences Research Grant (Strategic Outcomes Research Program for Research on Diabetes and Comprehensive Research on Diabetes/Cardiovascular and Life-Style Related Diseases) from the Ministry of Health, Labour and Welfare of Japan. The funding body has determined the goal of this study, that is, verification of the intervention for reducing patient dropout from regular diabetes treatment.

Conflict of interest

The authors declare that they have no conflict of interest.

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Correspondence to Mitsuhiko Noda.

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Izumi, K., Hayashino, Y., Yamazaki, K. et al. Multifaceted intervention to promote the regular visiting of patients with diabetes to primary care physicians: rationale, design and conduct of a cluster-randomized controlled trial. The Japan Diabetes Outcome Intervention Trial-2 study protocol. Diabetol Int 1, 83–89 (2010).

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  • Diabetes
  • Dropout
  • Regular medical care
  • Primary care physician
  • Quality of diabetes care