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Automated bolus advisor control and usability study (ABACUS): does use of an insulin bolus advisor improve glycaemic control in patients failing multiple daily insulin injection (MDI) therapy? [NCT01460446]

David A Cavan1, Ralph Ziegler2, Iain Cranston3, Katharine Barnard4, Jacqueline Ryder1, Claudia Vogel5, Christopher G Parkin6*, Walter Koehler7, Iris Vesper8, Bettina Petersen8 and Robin S Wagner9

Author affiliations

1 Royal Bournemouth Hospital, Castle Lane East, Bournemouth, BH7 7DW, UK

2 Diabetes Clinic for Children and Adolescents, Mondstr. 148, 48155, Muenster, Germany

3 Academic Department of Diabetes & Endocrinology Queen Alexandra Hospital, Portsmouth, PO6 3LY, UK

4 University of Southampton, IDS Building, Southampton General Hospital, Tremona Road, Southampton, UK

5 Internistisches Fachaerztezentrum, Rontgenstraffe 6-8, D-63225, Langen, Germany

6 CGParkin Communications, 219 Red Rock Road, Boulder City, NV 89005, USA

7 Walter Koehler, baseline statistics GmbH, Max-Joseph-Str, Mannheim, Germany

8 Roche Diagnostics GmbH, Sandhofer Straße 116, 68305, Mannheim, Germany

9 Roche Diagnostics, 9115 Hague Road, Indianapolis, IN, 46250, USA

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Citation and License

BMC Family Practice 2012, 13:102  doi:10.1186/1471-2296-13-102

Published: 13 October 2012



People with T1DM and insulin-treated T2DM often do not follow and/or adjust their insulin regimens as needed. Key contributors to treatment non-adherence are fear of hypoglycaemia, difficulty and lack of self-efficacy associated with insulin dose determination. Because manual calculation of insulin boluses is both complex and time consuming, people may rely on empirical estimates, which can result in persistent hypoglycaemia and/or hyperglycaemia. Use of automated bolus advisors (BA) has been shown to help insulin pump users to more accurately meet prandial insulin dosage requirements, improve postprandial glycaemic excursions, and achieve optimal glycaemic control with an increased time within optimal range. Use of a BA containing an early algorithm based on sliding scales for insulin dosing has also been shown to improve HbA1c levels in people treated with multiple daily insulin injections (MDI). We designed a study to determine if use of an automated BA can improve clinical and psychosocial outcomes in people treated with MDI.


The Automated Bolus Advisor Control and Usability Study (ABACUS) is a 6-month, prospective, randomised, multi-centre, multi-national trial to determine if automated BA use improves glycaemic control as measured by a change in HbA1c in people using MDI with elevated HbA1c levels (#62;7.5%). A total of 226 T1DM and T2DM participants will be recruited. Anticipated attrition of 20% will yield a sample size of 90 participants, which will provide #62;80% power to detect a mean difference of 0.5%, with SD of 0.9%, using a one-sided 5% t-test, with 5% significance level. Other measures of glycaemic control, self-care behaviours and psychosocial issues will also be assessed.


It is critical that healthcare providers utilise available technologies that both facilitate effective glucose management and address concerns about safety and lifestyle. Automated BAs may help people using MDI to manage their diabetes more effectively and minimise the risk of long-term diabetes related complications. Findings from a recent study suggest that BA use positively addresses both safety and lifestyle concerns; however, randomised trials are needed to confirm these perceptions and determine whether bolus advisor use improves clinical outcomes. Our study is designed to make these assessments.

Trial registration


Insulin therapy; Multiple daily injections; Diabetes; Randomised; HbA1c; Psychosocial; Hypoglycaemia