The study population – sampling

The present study was framed upon a grounded approach that incorporated a form of theoretical sampling, which is regarded as a central tenet of grounded analysis (McCann and Clarke, 2003a), which was recounted by Strauss (1987), who stated that theoretical sampling is a process where the researcher makes a decision as to what data needs to be collected, where from, and why, based upon current analytical output or initially informed through theoretical sensitivity. Charmaz (1990) provided a further purpose of theoretical sampling, whereby she regarded that it not only informs the analytical direction of the data collection (and constant analysis) of the data (whilst situated in the field), it also provides structure to the analysis. These were the methods that I used to determine the nature of my sampling / questioning approach and I had recognised that without having developed any pre-determined theoretical sensitivity I would, as a grounded researcher, have encountered a conceptual impasse as a researcher needs a starting point from which to establish the initial inquiry.

My sampling was initially informed through theoretical sensitivity, which was gleaned during a number of semi-structured interviews that I had conducted during a previous research study (Parnia, Spearpoint, de Vos et al, 2014). During these

interviews I became sensitised to an issue raised by participants in that many of them were not aware that they had actually had a cardiac arrest and had learned that they

had done so as a direct consequence of the consent process. This realisation prompted me to consider and question how informed patients had been during their recovery. This discovery was fundamentally influential to the development of the research questions in this study, furthermore it also theoretically informed the interview schedule, a similar experience to that outlined by Orona (1990) in her work on temporal identity loss.

Glaser and Strauss (1987) could have argued that my sampling method was akin to a selective or purposive sample, as I declared in my research protocol submitted to the research ethics committee that I planned to interview up to 30 patients that met my inclusion / exclusion criteria, however Draucker and colleagues (2007) offered a

detailed critique of contemporary approaches to grounded theory sampling methods that detailed a hybrid model of selective / theoretical sampling. Their model identified an evolving, changing sample that commenced with a small, theoretically informed

purposive sample, which as the research progressed became increasingly more theoretical, as a consequence of the constant comparative method. This was the sampling model that I had applied to the current study and my prospective recruitment strategy was designed to be efficient, utilising the most reliable information sources (patient databases) and communication methods (e-mail, telephone, face-to-face contact), which will be described in the forthcoming sections of this chapter.

As anticipated, my strategic approach became more meaningfully informed once I had conducted the first few interviews as the primitive themes and coding categories were conceptualised, a situation that had been identified by Glaser and Strauss (1967). Regardless of the source of theoretical sensitivity, sampling was at all times directed towards patients recovering from cardiac arrest and theoretical sampling/questioning was conducted rigorously during the analytical coding.

The inclusion criteria were comparatively easy to construct, but because of the potentially devastating sequelae associated with cardiac arrest survival, it was felt necessary to determine explicit exclusion criteria so as to provide as clear as possible delineation between those participants who could be approached for inclusion in the study and those would not be suitable, which was particularly useful when I made initial contact with the respective wards where the patients were located. Table 5. Below details the inclusion and exclusion criteria.

Table 5. Inclusion / Exclusion Criteria following recovery from cardiac arrest

Patients who regained consciousness

Patients who are able to communicate effectively. Patients who are able to understand or speak English. Patients who are able to provide informed consent. Patients are 18 years of age or older.

Patients who have not regained consciousness Patients who are not able to communicate effectively. Patients who are unable to understand or speak English. Patients who are unable to provide informed consent. Patients below 18 years of age.

The inclusion criteria were derived in order to facilitate reliable data capture through the in-depth interview approach, accordingly it was felt necessary to limit the criteria to exclude those patients who were considered unable to communicate

effectively through speech. Whilst it was recognised that this would potentially limit the sample and exclude a voice that would otherwise be unheard, the time constraints and the considerable difficulties associated with using a non-verbal approach to undertaking a detailed, complex interview, subject to theoretical sampling justified the exclusion criteria. A similar opinion was reached with regard to participants’ abilities to understand and speak fluently in English. Kapborg and Bertero (2002) utilised interpreters during qualitative interviews and identified significant interpretive complexities that undermined the validity of the data. Temple and Young (2004) acknowledged the missing voice of the deaf and / or non-English speaking patients whilst understanding the not

insignificant difficulties associated with trying to overcome the communication medium and language problems. In addition to the reliability of data interpretation, there were a number of implications surrounding the involvement of interpreters in the interviewing process within a clinical research environment, specifically their availability at short- notice and their availability for purposes of transcription, accompanied by the associated costs.

The initial plan was to conduct in-depth qualitative interviews with up to 30

surviving patients, or at least sufficient to reach a point of data saturation, a position that is reached when the frequency of novel data declines almost to a situation where little or

no new data emerges (Creswell, 2007), whereas Glaser and Strauss (1967) determined that sampling in grounded methodology is continued until theoretical saturation is

reached and hence it is difficult to pre-determine how many interviews may be

necessary. However, a recent detailed discussion amongst recognised expertise in the field indicated that there are many factors that should be considered when

contemplating the optimal sample size, which should include the ontological and epistemological stance taken by the researcher and the researcher should be

sufficiently rigorous in deciding that a sufficient sample size is achieved in the context of their inquiry (Baker and Edwards, 2012).

In the development of the study protocol I prospectively considered that the first two to three interviews would be directionally important to the continuing refinement the nature of the inquiry through my phrasing of the questioning and deeper probing of the theoretically informed areas (through constant comparison between each of the

interviews), but they were also considered as useful pilot interviews in helping to determine the appropriateness of the participant information sheet, the consent form and the outline interview schedule (appendix 1) as measures of good ethical practice (Royal College of Nursing, 2011), but this situation did not arise for the participants.