Consideration will now be given a description of the key research methods of this thesis that are coherent and consistent with IPA’s conceptual and epistemological base.
3.8.1. Sampling strategy.
It is a general criterion of IPA that the sample is relatively homogeneous, (Willig, 2001; Smith et al., 2009), with the ambition that participants, in addition to sharing experience of a phenomenon, “do not vary significantly across demographic characteristics,” (Langdridge 2007, p.58). This facilitates comparison across accounts and the development of a wider understanding of the phenomenon (Langdridge, 2007; Smith et al., 2009). In order to address the research aims of this thesis, it was important to be able to access GPs who could contribute their experiences of identifying and managing childhood obesity.
A decision was made to construct homogeneity on the basis of participants’ length of experience working in a primary care setting, and for the purpose of this thesis, this was defined as having been a GP for 25 or more years, which was deemed a sufficiently pertinent period of time to evidence significant experience of primary care consultations. This time frame has been used in other studies of GPs which have purposefully sampled on the basis of experience. For example Elwyn et al., (2000) used this time frame when exploring how experienced GPs involve patients in healthcare choices, and in McKeown et al’s., (2003) qualitative study of GPs’ attitudes to drug misusers and drug misuse services in primary care. The decision was based on two key factors. Firstly this group of GPs have not previously been purposefully sampled in the literature on childhood obesity, and therefore the research in this thesis would provide a new and additional contribution to the existing literature. Secondly the decision to purposefully sample on experience was assisted by Elstad et al’s., (2010) research on GPs and diabetes management, which focused on the skills practitioners acquire and develop throughout their clinical career. It concluded that GPs gain complex social,
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behavioural and intuitive experiential knowledge as well as the ability to compare the present day patient against similar past patients. Highlighting and exploring these active cognitive reasoning processes was felt to be an important component of this research topic of GPs’ experience and meaning making of childhood obesity. A practical decision was also made to restrict recruitment to this study from one PCT area, as defined in Chapter One, as it was felt that this would ease recruitment challenges and would secure sufficient numbers for a thesis which aimed to recruit ten participants.
The inclusion criteria therefore for eligible participants in this study were:
GPs who had been registered practitioners in a NHS General Practice partnership for 25 years and over.
GPs registered as partners on the Stockport PCT GP list (2009/10).
Whilst no further demographics were included in the inclusion criteria, descriptions of the GPs, their gender, patient populations, rates of childhood obesity, and the deprivation indicators of each practice are detailed in Appendix Eight. However, these are presented for contextual purposes rather than to highlight any claims of representativeness.
The exclusion criteria for the study were as follows:
Trainee GPs, GP registrars, newly qualified or GPs who had been in practice for less than 25 years.
Locum GPs.
The rationale for this exclusion criteria was again consistent with the IPA methodology, which does not support “maximum variation sampling” (Langdridge, 2007, p.58) but rather focuses on sampling which is purposive and homogenous. However, in identifying the above exclusions it was clearly recognised that further perspectives from trainee, newly qualified, younger GPs, or locum GPs would provide an equally valuable perspective. They may also provide a wider set of results that would enable a more comprehensive understanding of the population of GPs, and as such should be considered as a recommendation for future research.
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In IPA there is a consensus towards the use of smaller sample sizes (Smith, 2004, Reid et al., 2005). Whilst Smith and Osborn (2007) note that sample size depends on a number of factors and that there is no “right” sample size; as an idiographic method, they argue that small sample sizes facilitate greater analytical depth and an analysis of “potentially subtle
inflections of meaning” (2007, p. 519). Smith et al’s. (2009, p.52) later publications are more specific and recommend between four and ten interviews for a Professional Doctorate. However, sample sizes vary widely in IPA studies (Brocki and Wearden, 2006), who conclude that decisions about sample size and homogeneity should be made in the context of each individual study. For the purpose of this thesis, following considerations of time, resources, recruitment strategy and research question it was determined that the sample size would be 10 GPs, which would provide a sufficient perspective to explore the research question in depth. Guest et al. (2006) reviewed the concept of “data saturation,” (2006, p.59), that is the point at which no new information or themes are observed in the data. Using data from a study involving sixty in-depth interviews with women in two West African countries, they found that saturation occurred within the first twelve interviews, although basic elements for meta themes were present as early as six interviews.
3.8.3. Recruitment of participants.
In determining the recruitment strategy for this study a number of issues were considered. The initial consideration was to write to all GPs in Stockport asking them to participate in the study. However it was acknowledged that recruiting GPs to take part in research in primary care can be challenging (Mason et al., 2007). Studies have indicated that GPs report to being overwhelmed by requests to collaborate in research (MacPherson and Bisset, 1995; Smith et al., 2003) and research falls low on GPs’ list of priorities due to high workload, lack of interest in the areas and lack of financial compensation (Salmon et al., 2007). The literature review in Chapter Two has identified that recruitment of GPs to research on childhood obesity by letters of invitation tend to have a poor response rate (Redsell et al., 2011), or the respondents who do volunteer tend have a particular interest in childhood obesity, (Walker et al., 2007; Turner at al., 2009), whereas those GPs who are the least interested in the areas of childhood obesity are less likely to respond to the invitation (Redsell et al., 2011).
It was therefore decided that a more direct approach would be adopted and telephone contacts would be made to the purposefully sampled individual GPs. In order to facilitate this, the
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researcher obtained a list, from the PCT registered data base of all GPs who had been practising in Stockport for over 25 years, and the first ten on the list were approached directly via telephone and the research objectives were discussed. Eight GPs agreed to participate and two declined (one because he was about to start a secondment at a University and the second had very recently taken over a new practice), the next two GPs on the list were approached and they agreed to participate. Following the initial contact the respondents were sent the research information sheet and consent form, as presented to Salford University Ethics Committee in December 2010, (Appendix Four). The GPs were again given the opportunity to participate in the research and all agreed to do so.
There are both advantages and disadvantages in this approach. Firstly, the advantage was the researcher found it relatively easy to recruit participants to the study, possibly due to the fact that the researcher was previously known to the GPs and therefore was met with a favourable response at the initial telephone contact. Secondly, as Chapter 4 and Chapter 5 will indicate, there was clear evidence that some of the GPsperceived themselves to have a very limited role in supporting children who are obese, and probably would have been very unlikely to respond to a letter inviting them to participate in a study on childhood obesity. It could be argued that this approach was somewhat coercive. However this is unlikely as two of the contacted participants did not actually participate. Interestingly when the GPs were contacted many made it quite clear that they did not have any specialist interest or knowledge of childhood obesity, but agreed to proceed when it was confirmed that this was not a requirement of participation. The issue of the researcher’s prior contact with the GP participants is also covered in section 3.10, and in the limitation section of Chapter 5.
Appendix Eight provides a description of the participant demographics and the practice childhood obesity prevalence rates. In summary four of the participants were female and six males. Three of the GPs were British Asian and seven British. The year of qualification ranged from 1979 – 1985, at the time of the interviews the number of years working as a GP ranged from 26 years to 32 years. The practice list size ranged from 2,150 – 11, 687, and the number of partners in the practice from one to eight partners.
3.8.4. Method of data collection.
Individual semi-structured interviews with the GPs were felt to be the most appropriate approach which would enable them to respond as “experiential experts” (Smith, 2008 p. 18), and is a method of data collection that is compatible with the data analysis techniques of
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interpretive phenomenology (Willig, 2001; Langdridge, 2007).Whilst there are arguments for focus groups in IPA (Smith, 2004), in this instance the emphasis was on the individual experience of identification and management of childhood obesity and a focus group could have potentially clouded individual differences with the group dynamics. The practicalities of bringing 10 GPs from 10 different practices equally would have been challenging if not impossible. Similarly other methods of data collection, for example, reviewing case notes would have offered interesting insights, but this would not have enabled an exploration of how the GPs made sense of the clinical encounters with children who are obese.The benefits of using a semi-structured approach in qualitative research are well rehearsed (Mason 2002; Blaikie, 2007; Silverman, 2013), where it is acknowledged that this method enables the participant to articulate as much detail about the experience as possible (Langdridge, 2007).
3.8.5. Interview guide development.
The interview guide detailed in full in Appendix Seven, emerged following the review of the UK literature on the identification and management of childhood obesity in primary care, (Walker et al., 2007; Turner et al., 2009; Redsell et al., 2011) and a consideration of the range of issues to be explored within the research aims. The interview schedule centred on the major themes of understanding of childhood obesity by GPs, their approach to the identification and management of childhood obesity and their particular experiences with families and obese children during the consultation process. Table 3.1 details the key areas in the interview schedule.
Causes and implications of childhood obesity.
Impact of childhood obesity on the child and the family.
Experiences of identifying childhood obesity.
Decision making and experiences of raising the topic in the consultation.
Child and parental responses.
Experiences of managing the child who is obese in the consultation.
Support available to the child and family.
Resources and support available to the GP.
Experiences of working with obese children and their parents.
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The interview questions were designed to be relatively general, and focussed on the interaction between the GP and the child and family. The first sets of questions were primarily descriptive, open and scene setting, and the focus was on their views, ‘why do you think we
are seeing an increase in childhood obesity?’, and ‘what do you think is causing this?’ These were designed to enable the GPs to feel comfortable with the fact that the interview was focussed on their views and experiences, and it was not a test of their clinical expertise or knowledge of guidelines. Any leads opened up by the GPs were followed if it was perceived to be important to the GP or relevant to the experience of a primary care consultation. Later in the schedule the questions encouraged the GPs to be more evaluative and reflective about their own experiences, such as ‘how did it go?’, and more analytical ‘why do you think this is
the case?’ Leading questions which previous research had focussed on such as ‘the problem
of childhood obesity’ (Walker et al., 2007), and those which asked the participants to identify the ‘barriers’ to identification and management (Turner et al., 2009) were avoided. It was anticipated that this would reduce any presumptions about the GPs’ experiences or concerns and would not limit them to only one of a range of possible responses, thoughts, or feelings. The key areas to be covered in the research interview were presented in the introductory invitation letter, (Appendix Five) and highlighted during the telephone conversation with the GPs when arranging the interview time. The interviews took place either at the GPs’ surgeries or in an office at Stockport PCT and were carried out between January and March 2011. Each interview lasted between 30 and 40 minutes. With a participant’s permission each interview was audio-recorded and transcribed verbatim by the researcher. All the GPs were provided with a copy of their interview transcripts and the opportunity to comment on the transcript in order to maintain rapport and trust between the GP and researcher. No amendments to the interview transcripts were provided by any of the GPs. In addition two of the GPs agreed to read sections of the thesis, including the findings, discussion and recommendations section and provide comments and check on the credibility and plausibility of the findings.