Psychometric and biomedical outcomes of setting explicit glycated haemoglobin targets in adults with diabetes
: A mixed-methods parallel-group randomised feasibility study

Student thesis: Doctoral Thesis


The disease burden of diabetes can have wide-ranging implications on patients’ psychological wellbeing and health-related quality of life. Glycated haemoglobin targets are commonly used to guide patient management in diabetes to reduce future risk of developing diabetes complications, but little is known of the psychological impact of glycated haemoglobin target-setting.
To explore the feasibility of undertaking a conclusive study evaluating the impact of setting explicit glycated haemoglobin targets in adults with diabetes.
This single-centre randomised feasibility study used a mixed-methods approach consisting of a main study (A) and three supporting sub-studies (B, C, and D). In main study A, eligible adults with type 1 or type 2 diabetes completed baseline validated psychometric questionnaires evaluating health-related quality of life (EuroQoL-5D-5L), diabetes-related distress (Problem Areas In Diabetes), self-care (Summary of Diabetes Self-Care Activities), wellbeing (Well-Being Quetionnaire-12) and diabetes-related psychosocial self-efficacy (Diabetes Empowerment Scale-Long Form). Participants were randomised 1:1 into groups A and B. Participants in group A received explicit glycated haemoglobin intervention targets 5 mmol/mol above their current glycated haemoglobin readings. Participants in group B received explicit glycated haemoglobin targets 5 mmol/mol below their current glycated haemoglobin readings. Rates of eligibility, recruitment, retention and questionnaire response were recorded. Psychometric outcomes were re-evaluated 3-months post-intervention. Sub-studies B and C used qualitative semi-structured interviews to evaluate experiences, views and opinions of diabetes patients and healthcare professionals in relation to the acceptability of study processes, the use of glycated haemoglobin targets, the impact of diabetes on psychological wellbeing and, in sub-study D, barriers to participation in diabetes research.
Out of 109 eligible individuals, 50 (46%) participants were recruited and randomised to the feasibility study with 40/50 (80%) completing baseline evaluation and 33/50 (66%) completing endpoint evaluation. Questionnaire response rate was 71%. Endpoint evaluation revealed no significant between-group differences in patient-reported outcome measures or glycated haemoglobin levels. The overall process of setting specific glycated haemoglobin targets, resulted in improved levels of distress (-4.4, p=.009), self-efficacy (.25 [.09–.41], p=.004) and subsequent HbA1c readings (-2.8% [-5.0–-.7], p=.012), with non-significant changes seen in health-related quality of life (-0.024, p=.875), wellbeing (3.0, p=.346), and self-care. In results from the semi-structured interview sub-studies, interviews with people with diabetes demonstrated study processes were acceptable. Themes regarding glycated haemoglobin targets demonstrated specific motivators (e.g., target achievability, risk of complications, hypoglycaemia avoidance), demotivators (e.g., lack of understanding, lack of target achievability), thoughts on individualised targets (e.g., targets catering to functional and social needs, rather than biomedical goals), and lack of knowledge (e.g., lack of awareness that targets are individualised, information overload). Interviews with healthcare professionals corroborated important themes arising in patient interviews, centred around treatment targets (e.g., glycaemic target achievability, integrating patients’ goals with glycaemic goals), diabetes care (e.g., lack of training in managing psychological issues, importance of developing rapport, patient involvement in care decisions), psychological aspects (e.g., use of positive language, impact of psychological issues on self-management), and physical aspects (e.g., treatment burden, medication side-effects). Interviews with individuals declining entry into the quantitative study demonstrated key study-related (e.g., time commitments, interference with standard care) and person-related (e.g., disability) barriers to participation, aiding with identifying future areas for improved recruitment.
This mixed-methods study provides a novel insight into the psychological implications of glycated haemoglobin target-setting for people with diabetes in secondary care, as well as demonstrating feasibility of undertaking a conclusive study of this nature.
Date of Award21 May 2024
Original languageEnglish
Awarding Institution
  • Edge Hill University
SponsorsSt Helens and Knowsley Hospitals NHS Trust
SupervisorSIMON WATMOUGH (Director of Studies), GREG IRVING (Supervisor) & Ram Prakash Narayanan (Supervisor)


  • glycated haemoglobin
  • HbA1c
  • psychometric
  • Feasibility
  • Qualitative Research
  • targets
  • diabetes
  • self-management
  • mixed method
  • mixed methods design
  • Mixed-methods

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