Conceptual frameworks, concept maps and expert skeleton map

beliefs, and theories that supports and informs [the] research” (122). It also informs the study research design. In the field of education, researchers have developed tools to facilitate structured knowledge-building using techniques of visualisation. For example, “concept maps, mind maps, conceptual diagrams” (330) aim to facilitate knowledge building. These models of knowledge visualisation are qualitative methods used to understand and facilitate learning processes.

Novak and Cañas have developed the notion of concept maps and define them as “graphical tools for organizing and representing knowledge” (129). They display concepts related to the specific question one wants to address (“focus question”) and how they relate to each other. These concept maps and other related tools can be used by individuals, such as students, to facilitate their own learning.

The production of concept maps has spread from education into other fields (115, 124), such as health research where Trochim introduced a method for concept mapping, which is also called “group concept mapping” (117, 122, 125-127). It has been primarily used for research planning and evaluation (123, 124). It is:

“a mixed-methods participatory group idea mapping methodology that integrates well-known group processes such as brainstorming and unstructured sorting with the multivariate statistical methods of multidimensional scaling and hierarchical cluster analysis” (128).

Trochim differentiates this CM method from others that aim to visualise knowledge and concepts to structure an individual’s thoughts (128). Trochim’s approach allows for gathering various stakeholders’ inputs concerned with a particular topic to produce a structured conceptual framework (128,331,332). Within this framework, “the ideas are clustered in groups so that a complex set of ideas can be more readily understood” (128). The visualisation is produced by performing a multivariate analysis on qualitative data. These data are generally obtained through brainstorming among a group of key stakeholders to generate statements describing a specific issue, followed by a sorting-rating exercise of these statements. Trochim’s CM has mainly been used as a method for conceptualising abstract constructs and has been increasingly used as an integrated part of scale development (127,128). For instance, Conrad et al. (128) used CM to develop a structured conceptual framework of financial exploitation of the elderly in the USA. The concept map, in this case, was used to develop the measurement scale of this construct in the frame of care provision for elderly victims of mistreatment (129), and seemed most appropriate to the requirements of my work.

Therefore, I decided to use Trochim’s CM (128).

Other methods could be used to develop conceptual frameworks. For example, the Delphi method is often used with professional experts. It involves asking a panel of experts to generate statements (or answer a questionnaire). They are then iteratively asked their opinions on these statements by rating and commenting on them until reaching a consensus, generally obtained during three rounds of consultation (333). Other qualitative participatory methods, like focus groups, are often used in used in migrant health research and conceptualisation work (334,335). In both Delphi and qualitative participatory research, a qualitative analysis can facilitate the identification of themes describing the overall conceptualisation. In contrast, in CM, the overall conceptualisation is obtained in the form of a concept map using a statistical analysis of all individuals’ conceptualisations. CM visualises the outputs of the analysis as a map, and generates a framework that could be directly operationalised to develop a measurement tool. Each individual contributes to producing the content of the concept (during the brainstorming by generating statements), and then each individual produces his/her own conceptualisation (during the sorting-rating exercise). Thus, CM helps reach a consensus without an iterative process and uses all the statements to generate a consensual map.

CM was, for me, the best method to use in this thesis as it fitted within the mixed-methods methodology and pragmatic approach I chose. It enabled me to use quantitative methods, which was required as part of my studentship, and to involve different stakeholders (experts and LAWs).

I conducted two CM separately for experts and LAWs, mostly because I wanted to include their lived experience, and I anticipated that the level of understanding, abstraction and language between experts and LAWs may differ. I aimed to get inputs from experts with academic or non-academic expertise on issues related to labour exploitation along the hypothesised continuum (e.g. precarious work, or human trafficking) in the following fields:

health; sociology, social sciences or social work; policy, law or advocacy; economy, finance or business. This variety of knowledge would be captured into the same conceptual framework that could be used as an “expert skeleton” map (129) of the exploitation of migrant workers in manual low-skilled jobs. This notion of “expert skeleton” has been introduced by Novak and Cañas (129) for their individual concept mapping method. They have suggested that:

“For difficult topics – whether difficult for the students as determined by the teacher’s previous experience, or difficult for the teacher because of his/her background – using an “expert skeleton” concept map is an alternative. An “expert skeleton” concept map has been previously prepared by an expert on the topic, and permits both students and teachers to build their knowledge on a solid foundation. “Expert skeleton” concept maps serve as a guide or scaffold or aid to learning in a way analogous to the use of scaffolding in constructing or refurbishing a building”. (129; p.20)

Therefore, I decided to elicit an “expert skeleton” map using the variety of expertise described above. It would describe the key content, both theoretical and empirical, of the concept of labour exploitation focusing on migrant workers in manual low-skilled jobs. I foresaw this skeleton map as a standardisable framework that could be complemented by knowledge from different groups of migrant workers in manual low-skilled jobs themselves in order to achieve a thorough understanding of labour exploitation (325). It would be a robust theoretical framework that could potentially be adapted or expanded for different contexts and populations; for example, a specific population of migrant workers in manual low-skilled jobs at risk of being exploited.

The second CM was conducted with one such population. The LAWs were expected to share their direct experiences of labour exploitation, be it their personal experiences or those reported by colleagues or relatives. This CM with LAWs aimed to explore labour exploitation from their perspective and to assess potential cultural and contextual specificities by comparing it with the expert CM. The joint conceptual framework used the expert skeleton map as a basis to incorporate LAWs’ voices.

Table 2 below summarises for each objective the corresponding method used to address it and which chapter discusses these findings.

Table 2 Objectives, methods and corresponding results chapter

* LAWs stands for Latin American workers in manual low-skilled jobs in London