Using qualitative methods in developing an instrument to identify barriers to self‐care among persons with type 2 diabetes mellitus

Aims and objectives To develop a questionnaire to address barriers and self‐care behaviour among persons with type 2 diabetes mellitus. Background Several instruments are available in the literature to measure barriers to self‐care in this population, but many of them present limitations in its psychometric validation process, and lack of theoretical background. Design Content validation study using multiple qualitative methods. Methods A systematic review was conducted, and two focus groups with fifteen participants (n = 15) were analysed to identify key topics and categories concerning barriers and self‐care behaviour. These categories were used to generate items that were subjected to expert scrutiny, using the Delphi technique. The resulting list of items was tested for readability and comprehension by nine diabetic patients (n = 9), through cognitive interviews. The whole process was conducted in accordance with the Theory of Planned Behaviour. Results The mean age (standard deviation) of participants in the focus groups and cognitive interviews was 66·05 (8·47) and 63·11 (6·13) years, respectively. 46·7% of the members of the focus groups and 44·4% of those interviewed were female, and the mean duration (standard deviation) of their diabetes was 6·53 (3·17) and 4·89 (3·84) years, respectively. After the qualitative analysis, 27 codes were obtained. Thereafter, items were generated in accordance with the dimensions of this theory: attitudes towards the behaviour (n = 23), social norms (n = 13), perceived behavioural control (n = 17) and behavioural intention (n = 15). Conclusions A rigorous process of content validation with multiple methods was implemented to obtain an instrument aimed at addressing barriers and self‐care behaviour of patients with type 2 Diabetes Mellitus. Relevance to clinical practice An instrument theoretically rooted and supported on professional and patients' views is available to assess self‐care behaviours in patients with type 2 Diabetes Mellitus. The evaluation of its reliability and construct validity will determine the instrument's value and practical application in the clinical context.