Background Depression is a common comorbidity in type 2 diabetes. Studies have consistently shown that major depression is associated with decreased diabetic self-care behaviour. People with subthreshold depression experience greater functional impairment, have a poorer quality of life and use health services more than those without depressive symptoms. Although subthreshold depression impacts self-care behaviour, the relationship between subthreshold depression and diabetes self-care behaviour has not been systematically reviewed. The objective of this systematic review is to determine the association between subthreshold depression and self-care behaviour in adults with type 2 diabetes. Methods This protocol will follow the guideline of the Preferred Reporting Items for Systematic Review and Meta-Analysis Protocols 2015 (PRISMA-P-2015). A systematic search of literature will be conducted for observational studies reporting the association between subthreshold depression and self-care behaviour in adults aged 18 years or over and diagnosed with type 2 diabetes. Electronic databases including MEDLINE, EMBASE, PsycINFO, Emcare and CINAHL will be searched using predefined search terms. Title and abstract, full-text screening and data extraction of identified articles will be done by two reviewers independently. Discrepancies will be resolved by a third author. The methodological quality of the included studies will be assessed using The Joanna Briggs Institute (JBI) risk of bias tools. The review results will be presented in the form of narrative synthesis, and if sufficient studies are available and variability among the studies is low, a random effects meta-analysis will be done to quantify the result. Discussion This review will synthesise evidence on the association between subthreshold depression and self-care behaviour in type 2 diabetic adults. The findings will be useful to researchers and policymakers to determine the most effective approach to overall diabetes management. The review will also identify research gaps in the current literature and provide direction for future research in this area of study. Systematic review registration PROSPERO CRD42018116373 Electronic supplementary material The online version of this article (10.1186/s13643-019-1084-7) contains supplementary material, which is available to authorized users.

Aims Adherence therapy is a candidate intervention to improve medication adherence and clinical outcomes in patients with type 2 diabetes. The feasibility of conducting a trial of adherence therapy in this population has not been established. The objective of this study is therefore to test the feasibility of conducting a randomized controlled trial of adherence therapy in a Middle Eastern context. Design A single‐centre randomized controlled feasibility trial of adherence therapy in patients with type 2 diabetes. Methods We will undertake an initial cultural adaptation of a telephone‐delivered form of adherence therapy in four patients in a Middle Eastern context. Our subsequent feasibility trial will aim to recruit 40 non‐adherent diabetic patients that will be randomly allocated to receive eight weekly 30‐min telephone adherence therapy sessions delivered by a diabetes educator versus treatment as usual. Key outcomes of interest include the number of patients invited to take part in the trial that consent to participate and then go on to complete treatment. Result The findings of this study will determine the feasibility of undertaking a full randomized controlled trial of adherence therapy in patients with type 2 diabetes.

Adherence therapy has been shown to be an effective adjunct treatment in long-term conditions including hypertension. The purpose of this study is to review and critically appraise evidence on the effectiveness of adherence therapy as an intervention in adults with type 2 diabetes. A systematic search of clinical trials published between 2005 and January 2020 in databases was undertaken in October 2018 and updated in August 2020. Inclusion criteria were any clinical trials where the population under investigation was adults with type 2 diabetes and the experimental intervention was adherence therapy. Version 2 of the Cochrane risk of bias was used to determine the quality of the included studies. No studies met our inclusion criteria. However, four studies that we excluded at full text screening tested some of the components (e.g., problem solving) of adherence therapy. As is recommended when reporting empty reviews, those studies were synthesized to determine if useful information can be extracted. That no trials of adherence therapy have been reported in type 2 diabetes establishes a potentially important gap in knowledge. This review was registered in PROSPERO (registration number: CRD42019115216) after the initial searches were completed.