The aim of the interview study is to determine patient and health professional attitudes to using a ‘polypill’ to manage CV risk, as opposed to treatment to individual targets for blood pressure and cholesterol.
The understanding of factors that make people and practitioners keen or reluctant to initiate a ‘polypill’ strategy are critical to the success of an RCT comparing the two treatment strategies in question. People on medication find combination tablets convenient and easier to remember, but do not like the reduced flexibility and the potential problems with identifying the source of side effects. Beliefs and practices of GPs with regard to hypertension treatment vary and patient behaviour with regard to CV risk is heavily influenced by subjective factors. Therefore, qualitative interviews will be conducted, which are considered to be the most appropriate way to elicit people’s beliefs, knowledge and the meanings they ascribe to their experiences. A grounded theory approach will be used to guide sampling, data collection and data analysis.
Participants and Sampling
20 patients and 30 healthcare professionals (nurses and GPs) will be selected for interview. A further theoretical sample within each group will then be sought out, with selection guided by emerging data analysis in order to extend and challenge earlier data and interpretation, and test the integrity and credibility of developing analysis.Interviewing will continue until new concepts are no longer being generated and theoretical saturation (repetition of themes) is reached.
Patients Sampling Strategy
The researcher will identify a list of all the patients in the existing CVD and high risk groups in the anonymised dataset and then send a list of the identifying codes of all these patients to the practice. The practice staff will then de-anonymise these patients and will send them a Beliefs about Medicines Questionnaire (BMQ-General). Patients who return a completed BMQ questionnaire will be eligible for interview.
Sampling will be carried out on the basis of BMQ score group, CV risk status (existing CVD, high CV risk and on treatment or high CV risk and no treatment) and number of medications. A researcher will randomly select patients from each of these categories, ensuring that similar numbers of patients in each category are included. Other criteria that will be taken into consideration when selecting patients will be their age, gender, ethnicity and socio-economic status. The sample will attempt to reflect a range of these criteria.
Health Care Professionals Sampling Strategy
GPs and practice nurses from each practice will be asked to complete a BMQ - General questionnaire at the study outset. They will also be asked to complete a section regarding their gender, date of qualification and ethnicity for sampling purposes. Those returning the BMQ will be eligible for interview.
Sampling will be carried out on the basis of BMQ score group, practice size and practice socio-economic status (reflected in the Index of Multiple Deprivation (IMD) score of the practice location). A researcher will randomly select practitioners from each of these categories ensuring that similar numbers of practitioners in each category are included. Other criteria that will be taken into consideration when selecting practitioners will be the date they obtained their professional qualification, gender and ethnicity. The sample will attempt to reflect a range of these criteria.
Practice staff will then be sent an invitation letter and information sheet, inviting them to take part in an interview.
The data will be collected by confidential, face-to-face, in-depth interviews using a topic prompt developed from the literature and then modified and refined during the first interviews. The interviews will follow broad topic areas based upon the study objectives, but encourage respondents to discuss their perceptions and experiences freely. Patient interviews will investigate understanding and beliefs about the relationship between CV risk factors and outcomes and the acceptability of a ‘polypill’ strategy compared with current individual treatments. GP and practice nurse interviews will explore the prescribing decision and perceived personal, patient, clinical and financial barriers to prescribing. Experience of CV risk factor management will be explored from patient and professional perspectives, as will issues around concordance.