3.6 Sample
The sample for the secondary data collection was initially purposive and for the literature review needed to include the following search parameters: sustainability; Circular Economy; and sustainability and the Circular Economy (Cresswell and Cresswell 2018; Bryman and Bell 2015). It was essential for each academic source to have a minimum of one of these search terms in order to be included in the results and findings chapter.
The academic journals which have been used to evaluate the similarities and differences between sustainability and the Circular Economy also provided the opportunity for snowball sampling due to the initial academic source providing references which could then be used as additional sources of information (Saunders et al 2016; Bryman and Bell 2015).
The sample for the case studies were based upon the application of sustainability and the Circular Economy. The case studies for sustainability were based upon organisations who had applied and were reporting the use of the United Nations Sustainable Development Goals. The case studies for the Circular Economy were selected from the case studies which are publicly available on the Ellen MacArthur Foundation website (Ellen MacArthur Foundation 2017).
3.7 Reliability and validity
The issues of reliability and validity are dependent upon the research paradigm, in this case interpretivism, and the data collection and analysis decisions which include the use of secondary data and the mixed methods approach (Cresswell and Cresswell 2018; Saunders et al 2016; Bryman and Bell 2015). Within the interpretivist paradigm, reliability is lower in comparison to the positivist paradigm due to the research being context-specific making it difficult to fully replicate should the same research be carried out at a future point in time (Cresswell and Cresswell 2018; Bryman and Bell 2015; Neuman 2013). Validity, however, is often greater in the interpretivism, in comparison to positivism, due to the research being context specific thus providing a richer source of data on areas such as different business approaches to the integration of sustainability and Circular Economy principles (Cresswell and Cresswell 2018; Saunders et al 2016).
The selection of the mixed methods approach also has an impact upon reliability and validity and this is dependent upon the type of data which is collected and analysed (Cresswell and Cresswell 2018; Neuman 2013). The issue of validity in greater in the collection and evaluation of qualitative data due to it being context-specific; whilst the use of quantitative data supports higher levels of validity as this data can be replicated in future research (Saunders et al 2016; Bryman and Bell 2015).
3.8 Research ethics
Research ethics need to consider what is being researched and how the data is being collected and to ensure that this process does not create any harm for any of the research participants, including any those who may be providing primary data; the researcher and the university (Cresswell and Cresswell 2018; Saunders et al 2016; Bryman and Bell 2015; Resnik 2015). Research ethics often follows an established code of conduct and includes the addressing of potential ethical concerns such as informed consent; data confidentiality and anonymity and the right of research participants to withdraw from the process (Cresswell and Cresswell 2018; Jankowicz 2005; Lee-Treweek and Linkogle 2000). Whilst these ethical issues are particularly important in the collection
