Reviewer’s report Title: Development of a complex intervention to promote appropriate prescribing and medication intensification in poorly controlled type 2 diabetes mellitus in Irish general practice

The introduction is equally very clear. It provides a strong clinical rationale for the study, citing relevant literature to highlight the clinical 'problem' to be addressed, and the existing evidence base in this area. The intervention development approach (i.e. MRC guidance, and BCW) is also introduced in sufficient, concise detail for the readership of Implementation Science, who are likely quite familiar with these frameworks.