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Negotiating the qualitative-quantitative divide: the best of both

Shaun Thompson

The BERA Postgraduate Forum research symposium I attended provided me with the opportunity to present my work in a supportive and critically constructive environment, providing me with invaluable feedback and suggestions with regards to my next stage of research.

Approached from a critical realist perspective, where there is a clear distinction between ontology (ontological realism) and epistemology (ontological constructivism) (Maxwell 2012), qualitative comparative analysis (QCA) is based on the assumption that ‘there are often sufficient conditions for something to occur, but they are not necessary ones, except under specific circumstances whereby the ‘natural necessity’ is actualised’ (Gerrits and Verweij 2013: 171). Unlike the ‘closed systems’, under which experimental research usually takes place, the social world is an ‘open system’. Therefore, QCA sets out to understand the underlying causal mechanisms behind observed events, which are influenced by the complex context of the social world (Olsen 2009).

‘As a tool for data collection and analysis, qualitative comparative analysis (QCA) is positioned at the boundary of qualitative and quantitative research’

As a tool for data collection and analysis, QCA is positioned at the boundary of qualitative and quantitative research, drawing on in-depth case-based knowledge and the use of set theory to investigate the specific conditions under which certain outcomes occur, thus producing a formal method for analysing qualitative data, taking account of the specific contexts of the cases (Mello 2017; Olsen 2009; Schneider and Wagemann 2010).

Due to the complexity of mathematical problem-solving, a number of processes and frameworks are required, thus giving rise to a potentially large number of relevant conditions to analyse. In order to identify the most relevant conditions applicable to the purposive sample used within my study, a theoretical framework, based on Skemp’s theory of relational and instructional understanding (Skemp 1978), has been used to select the key conditions for the study.

Some of the main challenges presented within this approach are the calibration methods used to convert qualitative data into quantitative data for analysis, and ensuring strong internal and external validity of the method. To help overcome these issues, Schneider and Wagemann (2010) suggest that calibration is theory-driven, and that the iterative process between data collection and analysis is clear and soundly justified throughout.

The feedback from the Postgraduate Forum symposium enabled me to reflect in-depth on my specific research questions, which are essential to ensuring that the overall research design and methodological approach align, in addition to strengthening the justification of the selected samples used (Thomann and Maggetti 2017). This feedback has enabled me to redefine and operationalise my research question, thus providing me with the opportunity to align my questions and methodological approach more rigorously. As I continue through my early research career, I will certainly be looking to attend future research symposia in order to gain the supportive yet constructive feedback which has been fundamental to shaping my research design.


Gerrits L and Verweij S (2013) ‘Critical Realism as a Meta-Framework for Understanding the Relationships between Complexity and Qualitative Comparative Analysis’, Journal of Critical Realism 12(2): 166–182

Maxwell J A (2012) A Realist Approach for Qualitative Research, London: Sage

Mello P A (2017) ‘Qualitative Comparative Analysis and the Study of Non-State Actors’, in Schneiker A and Kruck A (eds) Researching Non-State Actors in International Security: Theory and Practice, London: Routledge

Olsen W (2009) ‘ Chapter 1: Realist Methodology: A Review Realist Methodology: A Review’, Realist Methodology (set), Benchmarks in Social Research Methods (series)

Schneider C and Wagemann C (2010) ‘Standards of good practice in qualitative comparative analysis (qca) and fuzzy-sets’, Comparative Sociology 9(3): 397–418

Skemp R (1978) ‘Relational Understanding and Instrumental Understanding’, The Arithmetic Teacher 26(3): 9–15

Thomann E and Maggetti M (2017) ‘Designing Research With Qualitative Comparative Analysis (QCA): Approaches, Challenges, and Tools’, Sociological Methods & Research: 1–38