Schedule of procedures and assessments.

BackgroundHbA1c targets guide diabetes management to reduce complications, yet their psychological effects are poorly understood. This feasibility study evaluated the practicality of conducting a definitive trial evaluating the impact of explicit HbA1c target-setting in adults with diabetes.MethodsWe conducted a randomised mixed-methods feasibility study. Adults with diabetes were allocated 1:1 to receive an explicit HbA1c target set 5 mmol/mol above (Group A) or below (Group B) their current HbA1c. Biomedical (HbA1c, blood pressure, BMI) and psychometric patient-reported outcomes were measured at baseline and 3 months. Quantitative data were analysed in SPSS using independent-sample t-tests or Mann–Whitney U tests for between-group comparisons, and paired t-tests or Wilcoxon signed-rank tests for within-group changes. Qualitative data from semi-structured interviews with patients and healthcare professionals were analysed using the Framework Method of thematic analysis in NVivo. Acceptability was assessed via interview, and mixed-methods findings were integrated through triangulation to enhance validity.ResultsFifty participants were recruited; 34% withdrew. Though not powered to determine statistical significance, no between-group differences were observed in HbA1c or patient-reported outcomes. Across groups, diabetes distress decreased, self-efficacy improved, and HbA1c improved. Interviews indicated high acceptability and identified key motivators (target achievability, hypoglycaemia avoidance) and demotivators (limited understanding, perceived unattainability).DiscussionA randomised mixed-methods approach to HbA1c target-setting is feasible and acceptable, providing methodological insights for a definitive trial.Trial registrationThe study is registered with the ISRCTN (registration number: 12461724; date registered: 11th June 2021).