To date, there is no standardised validated tool of migrants’ labour exploitation, nor is there a measure or operationalisation of labour exploitation using a continuum approach. The tools developed in both schools of thought have used a categorical approach. Definitions and tools used to conduct public health research on migrant workers’ exploitation, mostly the extreme forms, have been ad-hoc or untested for migrant worker samples (7,10,155,191). Therefore, I identified and compared tools that could be used to measure labour exploitation and related concepts without specifying a population.
2.5.1. Key measures
Most of the studies explicitly referring to labour exploitation in public health have covered extreme forms of labour exploitation, especially human trafficking and forced labour, as they are mainstream concepts. Though two studies explicitly assessed labour exploitation and health outcomes (7,155); they used indirect indicators at organisational level, which could be classified within the SDH school of thought.
Other tools have measured concepts related to labour exploitation using direct indicators, which have presented a clear way to identify ‘exploited’ victims (154,207–209): one focusing on a key measure for precariousness, corresponding to the lower part of the continuum;
whilst the other three have measured human trafficking, forced labour and modern slavery, corresponding to the extreme part of the continuum.
First, I will present first the indirect measures of labour exploitation, corresponding to the lower part of the continuum. Second, I will present the direct measures of labour exploitation, which will then be compared. This comparison led to developing the working conceptual framework on labour exploitation presented in section 2.5.2.
Indirect measures
Two social epidemiological studies by Muntaner et al. (2011; 2015) explicitly aimed to quantitatively assess the links between health and labour exploitation in workers in low-skilled jobs (nursing assistants) (7,155). They found that ‘workplace exploitation’ and ‘social class exploitation’ were associated with negative health. They used proxy indicators derived from a theoretical Marxist definition of labour exploitation. These were indirect measures of exploitation using information about the organisation to define whether the workplace was exploitative or not. While grounded in theory and being replicable, these indicators are not validated. Importantly, it is unsure whether what was measured is actually labour exploitation, hence their content validity, a crucial property in measurement, remains unknown (210).
Muntaner et al. (2011) explored social class effects at an organisational level, which they measured through proxies defined as follows:
“a firm’s ownership type (e.g., for-profit vs. not-for-profit/nonprofit) can serve as an organizational-level indicator of social class exploitation […] because for-profit institutions are privately owned and, as opposed to nonprofits, their managers are obliged by law to maximize the extraction of labor effort from their workers.” (155; p.28)
The proxy for workplace exploitation uses the notion of social class, which corresponds to Marxist conceptualisations (see section 2.2.3.a). In their article, ‘workplace exploitation’ is used interchangeably with the term ‘social class exploitation’, which their second study explores.
Muntaner et al. (2015) explicitly discuss ‘social class exploitation’ as a predictive factor of depression among nursing assistants (7). These authors measure it using two proxies: 1) the proxy used for ‘workplace exploitation’ in the previous study; and 2) a proxy for “managerial domination” measured as “bureaucratic management style (i.e. “by the book”), labor relations violations, and perceptions of labor management conflict” (6; p.273). They present exploitation as a relational determinant of health and highlight that their “focus on relational class mechanisms has implications for the level at which prevention efforts should be targeted” (6; p.280).
Direct measures
Direct measures of concepts related to labour exploitation measures offer a clear way to identify ‘exploited’ workers, provide a questionnaire or a list of operational indicators, and describe the methodology.
For the lower part of the continuum, I identified one measure, the Employment Precariousness Scale (EPRES) (79) that is in the SDH school of thought. It is a theory-based
scale that was developed using EMCONET’s research; and measures six dimensions:
‘Temporariness’, ‘Disempowerment’, ‘Wages’, ‘Rights’, ‘Vulnerability’ and ‘Capability to exercise labour rights’. It relates to Muntaner et al.’s proxies, however, this scale includes direct indicators that can be measured using a validated questionnaire. In contrast with the measures in the HR school, it focuses on “contractual features of precarious employment […]; and workplace social dimensions of precarious employment relationships, i.e., workplace power relations” (79; p.549).
For the extreme part of the continuum, where the conflation in terms matters for identifying victims entitled to support, I describe here three measures, one per term. First, the Vera Institute’s Tool for the Identification of Victims of Human Trafficking1 (TIVHT) is the only validated tool on human trafficking identified in the literature (208). It is a screening tool designed to improve the identification of human trafficking victims in the USA. It uses the US definition of human trafficking where the notion of ‘movement’ is dismissed, hence it also covers forced labour. It includes five dimensions: ‘Abusive Labor Practices’, ‘Physical Harm or Violence’, ‘Sexual Exploitation’, ‘Isolation’, ‘Force, Fraud, Coercion’ (143; p.6). Second, the ILO operational indicators for forced labour (ILO FLI) are the most widely used measures that help to identify victims of forced labour, including human trafficking. The indicators are similar to those in the TVIHT and include: ‘Abuse of vulnerability’, ‘Deception’, ‘Restriction of movement’, ‘Isolation’, ‘Physical and sexual violence’, ‘Intimidation and threats’, ‘Retention of identity documents’, ‘Withholding of wages’, ‘Debt bondage’, ‘Abusive working and living conditions’ ‘Excessive overtime’ (214; p.3). These indicators are categorised into low, medium and strong and are distributed into two main concepts (both needed to identify a potential victim): 1)
“Involuntariness” covering ‘unfree (forced or deceptive) recruitment’, ‘work and life under duress’, and
‘impossibility of leaving the employer’; and 2) ‘Penalty or menace of penalty’ corresponding to coercive measures, such as the use of threats and violence, or withholding of wages or passport. Two dimensions can be added to distinguish trafficked from non-trafficked forced labour, depending on the particular country’s laws: involvement of a third party (e.g. a recruiter); and cross-border “movement” (143; p.19). Finally, the Global Slavery Index (GSI) (154) is a complex composite measure of modern slavery, including forced labour and human trafficking. GSI uses several sources of information to estimate the number of modern slaves, including primary data collection (i.e. questionnaires rather than policy or secondary data). Compared to the TVHIT and ILO FLI that focus on coercion, it emphasises the deprivation of freedom, which the authors claim is “common to all forms of modern slavery” (148;
p.11). It is a direct measure, however, seems to focus on coercion and includes: asking
1 VERA tool was designed to capture human trafficking for the purpose of labour and sexual exploitation, but I only consider the labour exploitation aspects.
whether a person was forced to work by an employer, the employer kept him/her from quitting the job and if the person was offered work but ended up forced to do something else and not allowed to leave.
To have a preliminary idea of how the concepts measured overlap and differ, I compared the four direct measures, which led to the working framework discussed in the next section.
2.5.2. The working framework
The comparison of the measures’ content demonstrated that there was much overlap between the different tools.
Figure 3 represents the working conceptual framework of labour exploitation that guided the research design, and highlights where the concepts measured converged and diverged.
Appendix A offers a detailed version of this figure, in which different colours were used to distinguish the items from each measure. I hypothesised that the core components of labour exploitation would be indicated by the themes common to all the measures (the inner rectangle).
Note: Dotted line rectangles represent the dimensions hypothetically composing the concept of labour exploitation, and the added dimensions that may be specific to more extreme forms (forced labour and human trafficking), which require additional dimensions to be characterised. A question marks (?) is used to highlight the hypothesised concepts related to labour exploitation (plain line rectangles).
Figure 3 Generic framework of labour exploitation representing the hypothesised differences in the dimensions composing labour exploitation, forced labour and human trafficking All measures covered the themes represented in the inner rectangle, hence labelled labour exploitation. All items of the EPRES, representing the lower part of the continuum were included in this inner rectangle. This scale did not have items or themes that would be specific
to precariousness in comparison to the extreme forms of labour exploitation. In contrast, additional themes were necessary for exploitation to be considered more extreme, hence their position in outer rectangles. The presence of additional themes to distinguish modern slavery from exploitation, echoes Mayer’s view that slavery is wrong because of additional wrongdoings (132) (see section 2.2.1). This is also in line with Skrivankova’s idea that forced labour and human trafficking can be prosecuted using a criminal law framework in addition to breaches of labour law (see section 1.2.2.b).
The inner rectangle ‘labour exploitation?’ in Figure 3 presents the three themes that could hypothetically be the core dimensions of labour exploitation: ‘Conditions of employment’,
‘Working (and living) conditions’, and ‘Restriction of freedom.
The outer rectangles cover the items stemming from the three measures of extreme forms of exploitation (HR school-specific). Dimensions in the frames ‘forced labour?’ and ‘human trafficking?’ seemed specific to extreme forms of labour exploitation, as additional layers.
They could be categorised into two ‘dimensions’: ‘Relationship between the worker and employer’, and ‘Recruitment’. This implies that these additional factors may make a situation shift from a lower to an extreme form of exploitation. The worker’s relationship with the employer may shape core aspects of labour exploitation (e.g. coerce him or her), and recruitment may be mutually influenced by this relationship. I have suggested that aspects of
‘transportation’ are likely to be specific to human trafficking, as proposed in the Palermo protocol (139) definition and the ILO (143).
The next section builds on this comparison and describes the continuum approach that was taken in this research.