STUDY PROTOCOL published: 30 March 2021 doi: 10.3389/fpubh.2021.649447 Precarious Employment and Stress: The Biomedical Embodiment of Social Factors. PRESSED Project Study Protocol Mireia Bolibar 1,2† , Francesc Xavier Belvis 2,3 , Pere Jódar 2 , Alejandra Vives 4 , Fabrizio Méndez 2,3 , Xavier Bartoll-Roca 5 , Oscar J. Pozo 6 , Alex Gomez-Gomez 6,7 , Eva Padrosa 2,3 , Joan Benach 2,3,8 and Mireia Julià 2,3*† 1 Department of Sociology, University of Barcelona, Barcelona, Spain, 2 Research Group on Health Inequalities, Environment, and Employment Conditions (GREDS-EMCONET), Department of Political and Social Sciences, Universitat Pompeu Fabra, Edited by: Barcelona, Spain, 3 Johns Hopkins University – Universitat Pompeu Fabra Public Policy Center, Barcelona, Spain, Ingrid Sivesind Mehlum, 4 Department of Public Health, CEDEUS, Pontificia Universidad Católica de Chile, Santiago, Chile, 5 Barcelona Public Health National Institute of Occupational Agency, Barcelona, Spain, 6 Integrative Pharmacology and Systems Neuroscience Group, IMIM (Hospital del Mar Medical Health, Norway Research Institute), Barcelona, Spain, 7 Department of Experimental and Health Sciences, Universitat Pompeu Fabra, Reviewed by: Barcelona, Spain, 8 Transdisciplinary Research Group on Socioecological Transitions (GinTRANS2), Universidad Autónoma Tran B. Huynh, de Madrid, Madrid, Spain Drexel University, United States Evangelia Nena, Democritus University of The PRESSED project aims to explain the links between a multidimensional measure Thrace, Greece of precarious employment and stress and health. Studies on social epidemiology have *Correspondence: found a clear positive association between precarious employment and health, but the Mireia Julià mireia.julia@upf.edu pathways and mechanisms to explain such a relationship are not well-understood. This † These project aims to fill this gap from an interdisciplinary perspective, integrating the social and authors have contributed equally to this work and share first and biomedical standpoints to comprehensively address the complex web of consequences senior authorship of precarious employment and its effects on workers’ stress, health and well-being, including health inequalities. The project objectives are: (1) to analyze the association Specialty section: This article was submitted to between multidimensional precarious employment and chronic stress among salaried Occupational Health and Safety, workers in Barcelona, measured both subjectively and using biological indicators; (2) a section of the journal Frontiers in Public Health to improve our understanding of the pathways and mechanisms linking precarious Received: 04 January 2021 employment with stress, health and well-being; and (3) to analyze health inequalities by Accepted: 03 March 2021 gender, social class and place of origin for the first two objectives. The study follows Published: 30 March 2021 a sequential mixed design. First, secondary data from the 2017 Survey on Workers Citation: and the Unemployed of Barcelona is analyzed (N = 1,264), yielding a social map of Bolibar M, Belvis FX, Jódar P, Vives A, Méndez F, Bartoll-Roca X, Pozo OJ, precarious employment in Barcelona that allows the contextualization of the scope and Gomez-Gomez A, Padrosa E, characteristics of this phenomenon. Drawing on these results, a second survey on a Benach J and Julià M (2021) Precarious Employment and Stress: smaller sample (N = 255) on precarious employment, social precariousness and stress The Biomedical Embodiment of Social is envisaged. This study population is also asked to provide a hair sample to have their Factors. PRESSED Project Study levels of cortisol and its related components, biomarkers of chronic stress, analyzed. Protocol. Front. Public Health 9:649447. Third, a sub-sample of the latter survey (n = 25) is selected to perform qualitative doi: 10.3389/fpubh.2021.649447 semi-structured interviews. This allows going into greater depth into how and why Frontiers in Public Health | www.frontiersin.org 1 March 2021 | Volume 9 | Article 649447 Bolibar et al. Precarious Employment and Stress the experience of uncertainty, the precarization of living conditions, and the degradation of working conditions go hand-in-hand with precarious employment and have an impact on stress, as well as to explore the potential role of social support networks in mitigating these effects. Keywords: precarious employment, stress, health inequalities, stress biomarkers, social support networks, in-work poverty, insecurity, psychosocial risks INTRODUCTION Precarious Employment and Health: Employment Conditions as an Emerging Existing Evidence and Research Social Determinant of Health Challenges The last quarter of the twentieth century saw the emergence Precarious Employment: Definition and of a paradigm shift in understanding and explaining health Operationalization and health inequalities: the perspective of social determinants Precarious employment is a general term that refers to insecure of health. This approach emphasizes the conditions in which employment conditions, implying a deficit in some of the people are born, live, work and age, including health systems (1); dimensions of “employment quality” (7). The term “precarious” conditions (and relations) understood as being the result of the was coined by French sociologists in the early 1980s to describe unequal distribution of money, power, and resources according temporary or seasonal work (8). Nevertheless, there is still no to the social structure. Therefore, this perspective highlights consensus in the scientific literature regarding the definition of the need to consider socioeconomic inequalities to understand precarious employment. health inequalities and the need to study the mechanisms Social scientists often stress the importance of single whereby the social structure is embodied (i.e., the process of aspects such as insecurity, flexibility, chronic uncertainty, and “disease embodiment”). vulnerability. For years, many authors analyzed precarious Employment is considered one of the most relevant social employment using one-dimensional approaches such as the determinants of health. Given the central role of employment in temporary nature of the contract or the self-perception of job the organization of the social structure and in the definition of insecurity. However, precarious employment is a widespread people’s living conditions, its characteristics are key to explaining phenomenon that affects both temporary and permanent workers the health and welfare of workers, families and communities (2). and, therefore, heterogeneity between and within the different From this perspective of the social determinants of health, the types of contract warrants using a multidimensional construct effects of employment on health and well-being thus go beyond of precarious employment, not solely the analysis of the type a limited perspective on psychosocial, physical, chemical and of contract as a one-dimensional indicator (9). Accordingly, environmental risk factors that occur in the workplace, which in recent decades multidimensional approaches have emerged, focus on people’s immediate/proximal environment. It rather which address a broader view of the construct (10). understands employment as a historical phenomenon linked to Following this logic, for two decades, the GREDS- power relations between employers and workers, and to the EMCONET research group has made substantial efforts to particular forms of labor market regulation and the welfare state. operationalize the concept of precarious employment by In this regard, the expansion of neoliberal policies and developing the Employment Precariousness Scale (EPRES). It is changes in labor markets that took place in the late twentieth a multidimensional construct that has been empirically validated century, which led to the erosion of the “standard employment in several countries such as Spain, Chile and Sweden (11–15), relationship” and to the proliferation of flexible (sometimes and is currently being tested in Belgium and Finland. EPRES called “non-standard”) forms of employment (3), acquire is based on the conceptual work by Rodgers, who considered special relevance. Indeed, they led to profound changes four dimensions of precarious employment (temporariness, lack in employment conditions and relations through modifying of protection -individualized negotiation between employees collective agreements, limiting social security benefits or and employers-, vulnerability, and wages) (16) and two further deregulating contractual relations (4). The Great Recession of dimensions based on a qualitative study conducted in Spain (17) 2008 exacerbated these trends yet further. The economic crisis that pointed out the importance of the scope of rights to which and fiscal austerity policies eroded levels of social and labor workers are entitled and of their ability to exercise them in the protection, and the application of social and labor reforms workplace. As a result, EPRES has a total of 22 items divided brought about massive layoffs and a further decrease in the into six dimensions: temporariness (contract duration and protection of employment, leading to widespread unstable tenure), disempowerment (level of negotiation of employment unemployment (5, 6) and increased precarity of employment conditions), vulnerability (defenselessness to authoritarian conditions. In this scenario, precarious employment should take treatment), wages (low or insufficient; possible economic center stage in the agenda aimed at identifying and combating deprivation), rights (entitlement to workplace rights and social emerging contemporary threats to the health of the population, security benefits), and exercise of rights (powerlessness, in and to the generation of health inequalities. practice, to exercise workplace rights) (11, 18, 19). Frontiers in Public Health | www.frontiersin.org 2 March 2021 | Volume 9 | Article 649447 Bolibar et al. Precarious Employment and Stress EPRES has proved to be capable of capturing concisely the self-perceived health and household well-being (31). Research complexity of the forms of employment that define precarious using the EPRES multidimensional scale has shown associations employment and has therefore allowed studying its prevalence between precarious employment and poor mental health in and its association with health among the working population. Spain and Catalonia (9, 32, 33), and with poor self-perceived For example, using data from the EPRES for Spain, the prevalence health (9, 32). This relationship was also found in a sample of of precarious employment among salaried workers in 2005 was non-standard employees of Stockholm County (Sweden) (34). 48%, and 50% in 2010. Therefore, in this project we will use this Qualitative evidence collected in Spain from Spanish (17) and construct to measure precarious employment. immigrant workers (35) also confirms this finding. The Relations Between Precarious Employment and Challenges for Research Health Despite the growing evidence of the association between The various research approaches to precarious employment and precarious employment and health, social epidemiology studies health in flexible labor markets are a great but heterogeneous tend to focus on temporal trends and on patterns according to source of information. Research in social epidemiology has the social profiles of workers, but the explanatory mechanisms addressed this issue from three main angles, showing the harmful underlying this relationship, both in biomedical and in health effects of: (a) temporary employment; (b) perceived socioeconomic terms, have not yet been sufficiently studied (10, employment insecurity and staff restructuring and downsizing; 36). However, this is essential to design policies intended to and (c) multi-dimensional approaches to precarious employment improve health and quality of life, especially in respect of the most (10, 20–22). vulnerable workers, and to fight against health inequalities. This Instability or temporary employment is one of the most project therefore aims to fill this gap from the two standpoints: commonly used one-dimensional indicators due to its the biomedical and the socioeconomic, by means of a mixed- widespread availability. Although studies have generally shown methods design that enables pooling the existing partial evidence a positive association between temporary employment and on the complex web of consequences of precarious employment psychological morbidity, there is still heterogeneity in this field and its association with health and well-being. The two following of research. Some authors find that the mental and self-perceived sections deal with these two relevant aspects. health of temporary workers is worse than that of permanent ones (23), whereas others find no differences (24), and still others Precarious Employment and Stress find that it is even better (25). These disparities might be due to Stress is currently a major social problem, with considerable and the heterogeneity among temporary workers, which reinforces persistent effects at all levels. Several studies show that stressful the need for applying multidimensional approaches. Moreover, events are associated with poor physical and mental health a recent study shows that although the prevalence of precarious through psychophysiological mechanisms (37–39), which may employment is higher among temporary than permanent cause many health problems including cardiovascular diseases, workers, the association with poor mental health is greater metabolic syndrome, osteoporosis, and depression (40). The term among workers with permanent contracts than those with “stress” was first coined in the world of medicine in 1956 by temporary contracts, suggesting that precarious employment Selye (41) to refer to unpleasant environmental events and to might be more harmful for permanent workers (9). the physiological reactions they cause. But it was not until 1967 With regard to perceived employment insecurity, the results that psychiatrists Holmes and Rahe conducted population studies are more homogeneous and show a positive association with to examine the impact of stressful experiences (37). Subsequent various health outcomes (26, 27). Notwithstanding, this indicator definitions focused on the perceived imbalance between demand is based on perceptions, which may be influenced by external and the individual’s capacity to respond to it (under conditions in factors such as economic crises or staff downsizing. which the failure to resolve the situation has important perceived The relationship between precarious employment and health consequences for the individual), whereby two main components using multidimensional measures is still limited but has of stress are differentiated: its causes or environmental stressors, increased in recent years, proving to be an insightful tool to and its effects, that is, the subjective reaction consisting of an comprehensively address the relationship between precarious emotional component and one of cognitive perception. employment and health (28). In Canada, using an eight- Research analyzing the relationship between precarious dimensional approach, it was shown that some dimensions employment and stress is scarce. Although some studies have of precarious employment such as low income, lack of an analyzed this relationship using some of the one-dimensional annual pay rise, no overtime pay and a manual job preceded approaches mentioned above, including perceived job insecurity an increased risk of adverse health outcomes (29). To be and temporary employment (42, 43), to our knowledge, none more specific, the Canadian researchers identified that both has analyzed the links between multidimensional precarious strain brought up by precarity in the employment relationship employment and stress. Furthermore, stress in this field of considered as a whole and the strain resulting from the research is usually measured through self-assessed indicators, dimensions considered taken separately were related to several and the use of more objective measures such as biomarkers is still health indicators (30). Subsequently, again in Canada, precarious in its infancy. employment as measured by the Employment Precarity Index To measure stress from an epidemiological point of view, was associated with worse mental health outcomes and poorer various types of instruments have been developed, depending Frontiers in Public Health | www.frontiersin.org 3 March 2021 | Volume 9 | Article 649447 Bolibar et al. Precarious Employment and Stress on the theoretical approach used to address it (44). The first is related compounds in search of better biomarkers of chronic the environmental approach, which focuses on evaluating the stress (56). causes of stress or stressors. The second approach is psychological and is based on the individual’s subjective evaluation of how they deal with the stressful situation. The last is the biological Social Pathways of Precarious approach, which consists of measuring the activation of specific Employment and Health physiological systems involved in the response to stress (44). The nature and extent of precarious employment has multiple Moreover, to analyse stress, it is also important to note the effects on various social dimensions indirectly linked to duration of exposure to the stressor, i.e., whether exposure is employment and work (57), triggering a multiple social acute or chronic. vulnerabilization process that defines the “precarious condition” Epidemiological research has mainly relied on self-reported (58, 59). In addition to the direct impact that precarious measures of stress, leaving the biological approach rather employment has on health, there are four social consequences unexplored. However, the latter really allows capturing the actual of precarious employment that might have an impact on embodiment of stressors in altered biological processes and workers’ health: (i) the exposure to occupational risks factors offers an “objective” measure of stress that is less dependent suffered by precarious workers, (ii) impoverishment and material upon subjective assessments. Within this category, in recent deprivation, (iii) uncertainty, and (iv) the erosion of social years much attention has been given to the study of cortisol support networks (Figure 1). We consider these as being as a biomarker of stress. Cortisol is a glucocorticoid hormone pathways within which particular mechanisms operate to trigger released after stimulation of the hypothalamic-pituitary-adrenal adverse health outcomes. axis (HPA), which is activated by stress and interacts with the The first pathway that potentially explains the relationship immune system and the autonomic nervous system, which are between precarious employment and adverse health outcomes also involved in the body’s response to acute and chronic stress. involves the greater exposure of precarious workers to poor Cortisol can be measured reliably in various biological media. working conditions, including more adverse psychosocial factors. More specifically, blood serum and saliva have been used to Psychosocial risks can be defined as work characteristics or measure acute cortisol concentrations and urine for short-term conditions that undermine self-efficacy, job control and self- concentrations (45, 46). However, several studies addressing esteem, generating a stressful experience that exposes the stress in the workplace that used serum or saliva samples yielded individual to the risk of suffering physical and/or mental illnesses highly variable and even conflicting results (47). To a large (61, 62). Psychosocial risk models put the focus primarily on extent, this is because work-related stress factors are likely to conditions in the workplace and do not delve into the more have long-term effects, and the accurate representation of chronic general employment conditions as a possible determinant of stress levels in these samples is more difficult because of the a stressful psychosocial environment. However, some studies following: they are subject to the circadian rhythm of cortisol and comparing standard and non-standard employment contracts therefore suffer from poor long-term resolution (48); and, more have shown an overall picture of more adverse health-related importantly, they are highly reactive to acute and transient stress working conditions in non-standard employment contracts (63– factors, obscuring the influence of chronic stress factors (49). 65). Moreover, others also reveal that temporary employment is Accordingly, to study chronic stress the most suitable means associated with more passive, high effort types of jobs, with little to date is the extraction of cortisol from human hair. This demand for tasks and less autonomy (66). The literature focusing can provide valuable information about exposure to stress in on Europe suggests that temporary workers are more susceptible a defined period of time, which can be up to several months to suffering the negative consequences of internal flexibility (e.g., (50, 51): since hair grows at a rate of ∼1 cm per month, and odd working hours, shifts, variable wages, etc.) and from the hormones are transported from blood flow to hair follicles, point of view of work intensification, factors of discomfort, this method enables a retrospective examination of cortisol and even physical risks posed by the working conditions levels, allowing the establishment of a basal level and the (67). Additionally, evidence suggests that these adverse social consideration of stress events that have occurred during the experiences may be linked to the precarious employment status period of examination (i.e., length of hair analyzed) (51). itself (11). Hair cortisol concentration (HCC) has already been used in The other pathways refer to the cascade of consequences of occupational health research to study the relationship between precarious employment beyond the workplace. They might all one of the main chronic stressors, unemployment, and health. be considered forms of “social precariousness.” We differentiate According to this evidence, unemployment has been documented them with the aim of distinguishing analytically specific to have an impact on people’s health and to be associated with dimensions of such social precariousness related to material increased cortisol levels (52). It has also been reported that living conditions, the subjective experience of insecurity and male shift workers under the age of 40 had significantly higher social network configurations, as three distinct pathways whereby cortisol levels than day workers (53) and that an increase in precarious employment might be related to stress, health, perceived job insecurity is (slightly) correlated with higher levels and well-being. of cortisol (54). Nevertheless, the relationship between HCC and Following this logic, we identify a second pathway: different measures of self-reported stress is under discussion adverse living conditions. Precarious employment has major (51, 55), and some authors are already delving into cortisol’s consequences on the material level, creating situations of both Frontiers in Public Health | www.frontiersin.org 4 March 2021 | Volume 9 | Article 649447 Bolibar et al. Precarious Employment and Stress FIGURE 1 | Conceptual framework of precarious employment and the pathways through which it has an impact on stress and health (in black, the core elements addressed empirically in the PRESSED project). Source: Authors’ own based on the models of Benach et al. (60) and Julià et al. (19). absolute and relative deprivation. As the Foessa Foundation through which poverty has been noted to have a negative impact points out, the increasing flexibilization of the Spanish labor on mental health (77), but also on certain physical illnesses, market and the subsequent increase in precarious employment especially those related with the cardiovascular system (78). have emphasized an already stark problem, in-work poverty, Thirdly, precarious employment entails a social and subjective as one of the features characterizing households in the post- experience of vulnerability (79). The uncertainty and insecurity crisis context (68). Conditions such as underemployment and of existence can be considered a constituent element of discontinuity in employment are factors that contribute to the capitalism, which ensures the need for the working class to increase in in-work poverty (69). Indeed, since they have lower, sell its labor. However, with the rise of the neoliberal capitalist more variable and less predictable wages, precarious workers model, this trend has been exacerbated. The flexibility of the suffer the greatest pressure of wage flexibility and their income is labor market, the financialization of the economy and the highly insecure (70). Moreover, in most post-industrial societies weakening of the Welfare State (80, 81) are factors specific to the social protection schemes are tightly linked to employment and socioeconomic organization of the last 4 years that have helped its characteristics (5). Accordingly, most precarious workers do erode the social norm of employment (82), thereby questioning not meet the criteria to benefit from these social transfers and key the guarantees of social citizenship built on employment (81). services, including unemployment benefits, pensions, etc., which Castel (81) describes these guarantees and resources as the hinders workers’ social protection and the decommodification basis to which the worker can resort to govern the present of their income (70–72). Consequently, they are unprotected and command their future. They provide work with a statute from sudden income stoppages, thus being susceptible to that includes non-market guarantees such as the right to a material deprivation and debt. That being said, in-work poverty minimum wage, labor law protections, coverage for accidents emerges as a potential pathway or mediating mechanism of and illness, the right to retirement, etc. that protect the worker, the relationship between precarious employment and health. i.e., that will allow them to be able to deal with the main risks It is commonly assumed that the economic condition is one of of life, so that they are not condemned to living day after the most important factors determining people’s health, as it day in the anguish of tomorrow. Thus, precarious employment directly affects virtually all of the social determinants of health gives rise to great vulnerability to social contingencies or (such as housing, diet, etc.) (73, 74). Harsh material conditions risks that compromise individuals’ ability to ensure their of existence and feelings arising from absolute and relative social independence by themselves, leaving the most precarious poverty not only directly harm the physical health, but also lead population at the mercy of imponderables that can degrade their to exposure to psychosocial stress factors with a major impact social status (81). As a result, precarious employment hinders the on mental health, thus becoming the root of a large number capacity for agency and the self-perception of control over the of mental psychological disorders (75, 76). Indeed, stress, in future, limiting, and restricting temporary horizon-building (83). particular, through neuroendocrine mechanisms, is the channel Precarious employment spreads uncertainty, unpredictability Frontiers in Public Health | www.frontiersin.org 5 March 2021 | Volume 9 | Article 649447 Bolibar et al. Precarious Employment and Stress and the experiential condition of a limited, precarious existence literature suggests that people in more precarious situations often in the present (70, 84, 85), even among those who do not have smaller, less diverse networks (106); and that, given the suffer precarious employment, but may perceive it as a threat tendency to socialize with people of a similar socioeconomic (84). Through danger, destabilization, fear, and contingency, situation (107), networks of people in precarious situations also precarious employment generates modes of subjectivation, tend to be less capable of providing resources. In addition, the creating a generalized, permanent state of insecurity (85). This social capital in support networks is clearly distributed unevenly has a major impact on the structuring of the course of life and along the axes of inequality: such as gender, socioeconomic its main transitions. Precarious employment hinders making status, age or ethnic/migration background. Previous research fundamental decisions regarding personal and family life. Short, has shown that the impact of disruptive socio-labor events such as stable and predictable transitions to and within employment, unemployment has an unequal effect on social networks and their characteristics of a “Fordist” social structure in which life ability to provide social support depending on socioeconomic experiences were relatively standardized and homogeneous, have background, with the networks of people better positioned in given way to more protracted, non-linear, increasingly diverse, the social structure being more resilient (108). Considering the fragmented, and in some aspects less predictable transitions (86), multiple and somewhat contradicting evidence, we see the need limiting the capacity for agency in the development of one’s own to further delve into the capacity of support networks to buffer biography or life path. the impacts of precarious employment on stress and health. These experiences of insecurity, lack of control and In short, numerous studies have shown that these four future perspectives have been identified as powerful social aspects arising from precarious employment (i.e., degradation of stressors, which in turn can be linked to outcomes of adverse working conditions, material deprivation, subjective experience health and well-being (80, 87). Job insecurity, especially, of uncertainty, and weakening of informal support networks) has received particular attention, and has been identified are powerful explanatory factors of health and disease (95, 109– as a major mechanism linking flexible employment with 111), with potentially important synergistic effects among them. negative psychological well-being and several somatic health However, no study has analyzed precarious employment jointly outcomes (88). with the resulting complex web of socioeconomic factors to Finally, in this project we are interested in deepening into explain its link to health, and, more specifically, stress. the role of social support networks in the relationship between The following diagram graphically summarizes the theoretical precarious employment and health, particularly stress and model described above, whereby the authors hypothesize that well-being. Informal social networks (i.e., interactions between precarious employment can have a significant effect on stress, individuals and the resulting relational structures) are a source health and the quality of life of working people. of economic, material, emotional, and informative support (89– 91) and are particularly important among people and households Objectives who are in a position of greater vulnerability (68, 92). There Building upon the research challenges identified, the PRESSED is a long tradition of studies that demonstrate the relationship project has three main objectives: between support networks and health, highlighting the protective role of relational resources and support (93). In addition to their 1. To analyze the associations between multidimensional direct effect on health, Cohen and Wills (94) highlighted the role precarious employment and chronic stress among salaried of networks as a buffer, i.e., their ability to protect people from the workers in Barcelona, measured both subjectively and using potentially pathogenic influence of stressful events. Numerous biological indicators. studies prove this role for stressful labor-related situations, such 2. To improve our understanding of the pathways and as unemployment (95–98), job seeking (99), intense work (100), mechanisms linking precarious employment with stress, or employment insecurity (101). health, and well-being. However, some researchers point out that the extension 3. To analyze health inequalities by gender, social class, and place of precariousness might also lead to the erosion of social of origin for the first two objectives. support networks (shrinking family- and friends-based networks, community bonds, relationships created within trade unions METHODS AND ANALYSES and associations, etc.) (102, 103). Accordingly, precarious employment has brought about new forms of individualization General Research Design (85), causing the most precarious workers not to feel part The proposed research has a three-phase sequential mixed design of a caring community (70). In this vein, academic research (112): quantitative-quantitative-qualitative (Figure 2). In this has shown that characteristics of networks that surround an type of methodological design, each phase has a different sample individual (their “personal network”) reflect an individual’s life size and collects different types of data. These phases are strung course (104) as ties are created in sociability spheres in which together so that the partial results of the first phases can guide people engage throughout their lives (105). Hence the experience the sample selection of the subsequent phases. Thus, the study of precarious employment can leave a mark on the support population (i.e., salaried workers aged between 24 and 60 years in network that some precarious people have, eroding their capacity Barcelona) is studied by means of three different methodological for support and thus buffer the cascade of social stressors strategies that combine random and purposive sampling logics. that result from the experience of precarious employment. The This form of “mixed method sequential sampling” (113) acts Frontiers in Public Health | www.frontiersin.org 6 March 2021 | Volume 9 | Article 649447 Bolibar et al. Precarious Employment and Stress FIGURE 2 | Flowchart of the PRESSED project study design. Sequentiality and interpretive integration of the phases, methods, sample size and objectives. Source: authors’ own Phases 1 and 2 were conducted between 2018 and 2020, while Phase 3 will be conducted in 2021. as the basis for the transferability or generalization of the Phase 2: Survey on Precarious data obtained from the specific context to the wider context. Employment, Pathways of Precarization Therefore, it enables conducting a feasible, realistic project. As and Stress noted by Verd and López-Roldan (114), it maximizes both This phase involved conducting a survey on precarious the methodological and theoretical efficiency of the project. As employment, social pathways, and stress on a smaller, tailored regards the former, the fact that the results of the most extensive sample (N = 255) in order to examine the relationship data allow selecting cases that are the subject of more intensive between precarious employment and individuals’ stress levels analyses amplifies the object of study and grants robustness as a potential predictor of physical and mental health, and to the processes of inference, transferability, and generalization to identify the role of the hypothesized pathways (Figure 1) of results. As for the latter, integrating the different phases as explanatory factors of this relationship. In this survey, allows providing a comprehensive explanation of how patterns of participants’ perception of their stress level was measured association between precarious employment and stress are built. subjectively through questionnaires, and objectively through the quantification of cortisol levels in their hair and other compounds related to HPA and the gonadal axis as biological Phase 1: Current Status and Social Map of indicators of chronic stress. Precarious Employment Using Secondary Pressed Survey Sample Data Although the sample of this survey is small and not This phase was dedicated to reviewing the existing literature representative, its interest lies in the internal variability and relevant to the research objectives and to developing the “social comparability of results. In other words, it is designed to show map of precarious employment” drawing on secondary data, how cortisol in hair (and other related biomarkers of the HPA specifically the Survey on Workers and the Unemployed of axis) is distributed throughout the whole range of experiences of Barcelona (EPYPB, 2017-2018). The EPYPB (N = 1,264) was precarious employment identified in the previous phase, and to particularly useful for this phase as it aimed at studying in unravel the explanatory power of the pathways and mechanisms depth the diversity of precarious employment situations and the of interest. On the other hand, this sample size, under the resulting social processes in the city of Barcelona. As a reference assumptions of an alpha risk of 0.05 and a beta risk below 0.2 population it took individuals of legal working age, living in the (80% power) in a two-sided test and with a sample loss rate of city of Barcelona and who had worked at least1 h during the 0%, will allow us to estimate correlation coefficients of 0.175. reference period. For further details of the survey see (115). Accordingly, a non-probabilistic sampling strategy was The main objective of this phase of analysis was to identify implemented, based on proportional quotas by sex, age group the prevalence and distribution of multidimensional precarious (25–34 years vs. 35–60 years), place of origin (born in Spain vs. employment among the wage-earning population and the most born abroad) and socioeconomic level of district of residence affected social profiles. The results contextualized and framed the (medium, medium-high or high vs. medium-low and low- subsequent phase’s results establishing the scope of Phase 2 at a income districts) (see Table 1). Participants were recruited population level, according to the general map drawn in Phase 1. from the pool of participants in the 2017 Barcelona Health This theoretical and empirical work allowed refining the project’s Survey within the selected age range who had agreed to being model and methodological design. contacted again for future studies and agreed specifically to being Frontiers in Public Health | www.frontiersin.org 7 March 2021 | Volume 9 | Article 649447 Bolibar et al. Precarious Employment and Stress TABLE 1 | Characteristics of the PRESSED survey sample. items on job contents and requirements; active work, influence and performance; social support in the workplace; quality of Born abroad Born in Spain Total leadership; and esteem. Age 20–34 Age 35–60 Age 20–34 Age 35–60 Working Poverty Medium-high or high income districts The questionnaire followed the AROPE methodology (117), Women 4 10 11 31 56 which relates to the financial situation of the household and takes Men 2 8 11 28 49 three forms of poverty into account: work intensity of household Medium-low or low income districts members, material deprivation, and relative poverty. To this Women 6 13 12 43 74 end, the household composition and the labor participation of Men 7 12 14 43 76 all its members during the year prior to the interview were Total 19 43 48 145 255 reconstructed. Interviewees were asked about the joint income of all of the household members, taking into account income from work as well as social benefits and other patrimonial revenues to calculate the equivalized disposable income. This indicator is contacted by the University for this project (n = 1,210). Also, calculated considering household members as consumer units in order to offset the bias of this subsample toward profiles whose weighting varies according to the number of household with higher levels of education and income, the abovementioned members and their ages (1 to the first adult, 0.5 to the second and recruitment strategy was complemented with 40 individuals each subsequent person aged 14 and over, and 0.3 to each child contacted through social and labor organizations that work with aged under 14). In OECD countries, people living in households groups of precarious workers and a slight overrepresentation at risk of relative poverty are commonly defined as having an of immigrant women. Interviewees were rewarded for their income of <60% of the median wage. The reference community participation with a courtesy gift of 30e. considered for this study is that of Barcelona, whose poverty line Inclusion criteria were: (i) being a salaried worker or bogus threshold for a unipersonal household, according to the 2016 and self-employed worker serving a single employer, (ii) being 2017 survey on living conditions, was 11,122.40 euros per annum between 24 and 60 years old, (iii) living independently in (926.90 euros per month). Barcelona (i.e., young people living with their parents were To measure material deprivation [considered by Crettaz excluded), (iv) the length of hair at the back of the head being of at (118) a more sensitive indicator in the lower part of income least one centimeter, and (v) not having taken holidays within the distribution], the subjects were asked about the availability of month prior to the interview. Exclusion criteria were: (i) having items included in the AROPE battery, alongside three further taken corticosteroids within the month prior to the interview, (ii) items related to the availability of internet, computer, and leisure. being diagnosed with an adrenal disease, and (iii) being pregnant, due to possible alterations in cortisol levels. Uncertainty Questionnaire, Indicators, and Variables This item was collected using information concerning various The questionnaire, requiring ∼40 min to complete, included aspects. First, perceived job insecurity. Perceived insecurity questions on the different topics of interest of the study as well as measures include measures oriented toward the perceived standard questions on sociodemographic characteristics. Below likelihood of the occurrence of an event (cognitive insecurity) we set out how the concepts of precarious employment, working and the emotional assessment or worry that this event conditions, poverty, uncertainty, social support networks, and causes (emotional insecurity). Both measures are applied to stress were operationalized and recorded (for further details on three domains of job insecurity: losing employment (job the questions included in the questionnaire, see Table 2 and the loss insecurity), finding alternative employment (labor market full questionnaire in Spanish, in the Supplementary Material). insecurity), and the worsening of working conditions (working conditions insecurity) (80). Second, financial insecurity was Employment Precariousness included, measured through the amount of time the interviewee EPRES, which consists of 22 items structured into the would be able to live without income before being in a serious abovementioned six dimensions: temporariness, wages, rights, financial situation. Third, capacity of exerting agency, which capacity to exercise rights, disempowerment, and vulnerability involved three questions inspired by PEPÍN (119) concerning the to authoritarian treatment. To further describe the job of the existence of limitations for major expenditure, personal projects interviewee other questions were included such as occupational or future plans due to the employment situation. Finally, the status, sector of activity, company size, and the performance previous labor market trajectory was considered; in particular, the of supervisory tasks. Finally, several questions related to the experience and duration of both unemployment and unstable or working day (such as doing overtime, involuntary part-time informal employment prior to the interview. work, the ability to take breaks, etc.) were also added. Social Support Networks Working Conditions The Duke-UNC Functional Social Support scale (DUFSS) was Psychosocial risks. A selection of questions was included from used, which measures perceived functional social support, the CoPsoQ questionnaire (version 3) (116), which includes basically emotional support in the affective and confidential Frontiers in Public Health | www.frontiersin.org 8 March 2021 | Volume 9 | Article 649447 Frontiers in Public Health | www.frontiersin.org Bolibar et al. TABLE 2 | Detail of the variables included in the PRESSED survey questionnaire. Control Surveyor ID Questionnaire number Interview date and time (start, end) Sociodemo- Sex Date of birth Place of birth (other Nationality District of residence Level of education graphics country: which?) Occupational Company activity Occupation Additional jobs Company size Supervision Existence of trade (descriptive) unions Employment Working day Contracted and real Preferred working Overtime Working days/month Advanced notice of Type of working day precariety hours hours Volunteering? longer than 10h, schedule changes Compensation? weekends EPRES Temporariness Wages: Disempowerment: Vulnerability: Rights: Exercise of rights: Contract type, Categories scale and Working day decision, For complaining, Parenthood, pensions, Days off, holidays, Duration, no. of annual Wages decision powerlessness, unemployment family leave, personal Tenure payments; Covers dismissal, authoritarian compensation leave, sick leave needs, treatment, replaceable Unforeseen expenses Various 2nd job Supplementary jobs? Actual hours Contract type Seasonality insecurity Working Psychosocial risks Contents and Active work, influence Social support in the Leadership quality (6 Esteem (2 items) Conditions requirements (7 items) and development (6 workplace (8 items) items) items) Other occupational Discrimination, violence 9 risks (2 items) Domestic Double burden (4 Proportion of Domestic chores Care workload + hours workload items) household chores outsourced of dedication assumed Life conditions Risk of poverty Household make-up: Months and hours Household income (all no. of people, ages worked prev. year members, all sources) (respondent and (open, if no answer: household members) bracket + Threshold) Material deprivation 9 AROPE items + Getting to the end of leisure, internet, the month computer Uncertainty/ Job insecurity Emotional insecurity Cognitive insecurity Insecurity (job, labor market, (job, labor market, hours, wages) hours, wages) March 2021 | Volume 9 | Article 649447 Financial insecurity How long could be Precarious Employment and Stress without wages Agency Ability to cover a major Postpone projects or Ability to make future expenditure major changes plans Trajectory Unemployment Unemployment in last Total duration of Length of last event Age 1st employment 10 years unemployment 10 Unemployment years (Continued) Bolibar et al. Precarious Employment and Stress subdimensions (120). This scale has also been validated for the case of Spain (121). This information was supplemented with four items of perceived availability of instrumental support, inspired by the Interpersonal Support Evaluation List (ISEL) Biomarkers questionnaire (122), as well as with questions concerning participation in civil society associations or organizations that provide support to citizens. smoking; alcohol; sport Perceived Stress Activities to reduce Use and habits: The questionnaire measured perceived stress in several ways. stress (open) In the first place, the questionnaire included the Spanish 2.0 version of the Perceived Stress Scale (PSS), based on the full 14- item version by Cohen (123), and adapted by Sanz-Carrillo et al. (124). In the second place, a question regarding workplace stress (125) was also used. Finally, the questionnaire included items Cognitive symptoms (4 concerning physical and cognitive symptoms of stress included Functional limitations Informal last 3 years in the CoPsoQ questionnaire, as well as open questions about the existence of stressful events in the previous month and the performance of activities to reduce stress. items) Health The questionnaire included questions about mental health and with family and friends Physical symptoms (4 Receive services from Prevents doing things Indef. contract last 3 well-being using the WHO-5 scale (126), self-perceived health, Participation at the the subject’s height and weight to calculate body mass index, the existence of functional limitations, and healthy habits relating to Medication workplace Incidents tobacco and alcohol consumption and to physical activity. NGOs items) years Hair Sampling and Analysis Procedure Upon completing the questionnaire, a sample of participants’ hair Workplace stress (AIS) counseling, car, e300 In quality of family life No. contracts last 3 equivalent to a lock of hair of the thickness of a pen (between ∼30 Other instrumental Height and weight support: housing, and 50 mg) was taken from the back of the head using scissors employment cutting as close to the skin as possible. The samples were taken by Comments Intensity the interviewers, who were trained to that end. years The first centimeter of the lock of hair that is in contact with the scalp is the biological material subjected to laboratory analysis. Since hair grows about one centimeter per month (127), Contact details: phone, In personal and family the selection of this segment implies that the level of chronic DUFSSS (emotional well-being (WHO-5) Stressful life events Mental health and stress accumulated over the month prior to sampling can be identified. The analysis was carried out using a LC-MS/MS (liquid chromatography-tandem mass spectrometry) validated Instability support) method (128). From this analysis, 11 targeted compounds were Type mail life quantified (see Table 3). In particular, eight of them belong to the HPA axis, which is considered to play a central role in the Participation in orgs. Perceived Stress Scale physiological response to stress. Cortisol and its metabolites were Self-perceived health situation interferes included, as well as other related compounds. Employment recontacting Possibility of Data Analysis Support It is planned to perform partial analyses using linear regressions (PSS) to delve into the association between precarious employment, the different pathways and indicators of stress, and well-being. TABLE 2 | Continued It is also planned to perform mediation analysis with structural Miscellaneous equation models to evaluate the project’s conceptual model Networks (Figure 1) as a whole. All analyses will be stratified by sex, and Health Stress biomarker predictors will be controlled, at least, for age and body mass index. Frontiers in Public Health | www.frontiersin.org 10 March 2021 | Volume 9 | Article 649447 Bolibar et al. Precarious Employment and Stress TABLE 3 | List of biomarkers of the hypothalamic-pituitary-adrenal axis (HPA) and the study. Criteria for their selection will be based on their gonadal axis obtained by LC-MS/MS analysis of hair samples (abbreviation and level of precarious employment, the type of association shown full name). between precarious employment and stress, and according to the Abbreviations Biomarker name identified role of the explanatory pathways. Due to the outbreak of the COVID-19 pandemic between F Cortisol survey data collection and the implementation of the qualitative 20αDHF 20α-dihydrocortisol interviews, and the resulting social and economic crises that 20βDHF 20β-dihydrocortisol caused (and are still causing) a major impact on the labor market, E Cortisone the linkage between the qualitative and quantitative phase of 20αDHE 20α-dihydrocortisone the study might be hampered. In order to overcome this issue, 20βDHE 20β-dihydrocortisone we plan to re-contact cases prior to the interview to update or βCortolone β-cortolone confirm the validity of the data obtained in the survey conducted A 11-dehydrocorticosterone in the previous phase. T Testosterone AED Androstendione Prog Progesterone DISCUSSION Promoting inter- or transdisciplinary scientific research is often proposed as a way to advance science and to expand its Phase 3: Qualitative Depth on the Link boundaries beyond the objects of study and theoretical and Between Precarious Employment and methodological approaches common to each discipline or area Well-Being of knowledge. However, there are few benchmarks on how Finally, following the logic of an intensive analysis of case studies to concretize interdisciplinarity in the practical aspects of as a final phase in a mixed-methods sequential investigation, a research projects. Thus, this protocol provides an example of sub-sample of the previous survey (N = 25) will be selected. interdisciplinaryty in the approach to and the development of With this sample, semi-structured qualitative interviews will be the methodological design of a research project on occupational conducted to look in greater depth into how and why precarious health. Furthermore, both the interdisciplinary approach, the employment and the associated social precariousness have an design of a mixed methodology (combining quantitative and impact on stress, health and well-being. qualitative data) and, especially, the use of biomarkers, are Thus, the aim of this third phase is to deepen qualitatively innovative elements in the treatment of this subject, hence the into the understanding of the particular mechanisms that results are expected to be able to provide innovative evidence of explain or predict the link between precarious employment relevance to the scientific community. and stress considering the complex casuistic of life situations Moreover, on a more general level this project should that contextualize each case. This qualitative phase supplements contribute to the “paradigm shift” led by the World Health previous results in the sense that it allows, first, identifying Organization’s Commission on Social Determinants of Health in the logical relationship established between the dimensions its influential report of 2008, which aims to recognize the real of precarious employment, and stress and health. Following weight of socioeconomic determinants as fundamental causes of the “process tracing” method of Bennett and Elman (129), health inequalities. Thus, the PRESSED project can help change work will be carried out with a procedural notion of the the view held by society and much of the scientific community on observed phenomena. This is a common method used within the causes of illness, currently dominated by explanations related the qualitative framework of case studies, which have a to behavioral and biological factors. small sample size and work with a notion of causality Second, this project is expected to have a social and economic not based on correlation and covariance but on identifying impact. In line with the principles established by the 2030 mechanisms and processes that connect causes and effects. Agenda for Sustainable Development, the project aims to Second, it also allows obtaining information on difficult aspects promote sustained, inclusive and sustainable economic growth, to harness via standardized questionnaires. In this sense, full, and productive employment and decent work for all, the flexible and open nature of semi-structured interviews and therefore help to reduce social inequality and enhance will allow deepening into the subjective perception of stress social cohesion. Given that the deterioration of the quality of and discomfort and the subjective experience of precarious employment conditions and subsequent precarious employment employment and associated pathways of social precariousness. is a phenomenon gaining importance in the context of post- Moreover, qualitative methodologies will be applied in the industrial economies, but especially in the Spanish context of interview to reconstruct the configuration and changes in social (non)recovery from the Great Recession of 2008 compounded support networks (130). These interviews will be analyzed by by the impact of the Covid-19 pandemic, there is a need for means of an interpretive, qualitative content analysis supported research projects that provide evidence of the most harmful and by Atlas.ti. unsustainable aspects of this model of employment, and of the Cases will be recruited from among survey participants who pathways and mechanisms whereby it plausibly causes such a have consented to being re-contacted for the next phase of negative, inegalitarian impact. Frontiers in Public Health | www.frontiersin.org 11 March 2021 | Volume 9 | Article 649447 Bolibar et al. Precarious Employment and Stress More specifically, the PRESSED project research results are Other social organizations and public health entities are expected to culminate in the proposal of scientifically informed expected to collaborate both in attracting participants for public policies. The project will end with the drafting of a the study and in disseminating the research results: Public document of recommendations for the design of social, labor, Health Agency of Barcelona (ASPB), trade unions and social and health policies aimed at refining epidemiological surveillance associations, notably the trade union Comisiones Obreras de systems and ultimately improving the health, well-being and Cataluña (CCOO - Workers’ Commissions), the Confederació quality of life -especially of the most vulnerable workers, and fight General de Treball a Catalonia (CGT - General Confederation the pressing health inequalities that currently exist. of Labor), and social movements such as No+Precariedad (“No more precarity”), Las Kellys (“The Maids”), and Mujeres ETHICS AND DISSEMINATION Migrantes Diversas (“Diverse Migrant Women”), among many others. Ethics This study was reviewed and approved by the Institutional ETHICS STATEMENT Commission for Ethics Review of Projects (CIREP) of Universitat Pompeu Fabra (UPF) under CIREP nr.0079. The studies involving human participants were reviewed and Written informed consent was obtained from all participants approved by Institutional Commission for Ethics Review of prior to participating in the study, and participants were Projects (CIREP) of Universitat Pompeu Fabra (UPF). The reminded that they can withdraw at any time. All data used patients/participants provided their written informed consent to in this project are duly processed, preserving data anonymity participate in this study. and confidentiality, fulfilling all legal and ethical requirements, and in compliance with the laws of Spain governing personal data protection. AUTHOR CONTRIBUTIONS Dissemination MB and MJ are PIs of the project and have led the writing of the The PRESSED project has an engagement, dissemination, manuscript. FB, PJ, FM, XB-R, OP, AG-G, AV, EP, and JB have and impact plan in order to maximize the social outreach provided theoretical and technical advice and have revised and and transfer of results. Its dissemination strategy aims accepted the manuscript. All authors contributed to the article to reach academia, stakeholders, policy makers and the and approved the submitted version. general public. First, academia, by publishing scientific articles in specialized peer-reviewed journals, conference papers FUNDING and reports on the website of the GREDS-EMCONET research group and in the UPF e-Repository. Second, This work was supported by the Spanish Ministry of Science, stakeholders, policy makers and the general public through Innovation and Universities under the research grant informative reports setting out the results, and press Precariedad laboral y estrés: factores sociales con impacto releases in the media and social networks. By the end of biomédico, ref. CSO2017-89719-R, funded by the Agencia the project, a conference will be organized to present and Estatal de Investigación (AEI) and the European Regional discuss the findings, which will be open to and promoted Development Fund (ERDF), EU. MB was a Serra Húnter Fellow. among stakeholders. She also conducted part of this work while holding a Juan de In order to strengthen social outreach and the transfer of la Cierva Incorporación fellowship (Ref. IJCI-2017-33999). results to the second target audience, the PRESSED project has EP holds an FPI fellowship (Ref. BES-2017-080100) from the aroused the interest of three institutions that have formally Spanish Ministry of Science and Innovation. JB gratefully expressed their interest in the results of the project. The acknowledges the financial support by ICREA under the ICREA following are PRESSED project Observer Promoter Entities Academia program. (EPOs): Institut de Seguretat i Salut Laboral (ICSSL - Institute of Occupational Safety and Health) of the Generalitat de Catalunya SUPPLEMENTARY MATERIAL (Government of Catalonia), European Trade Union Institute (ETUI), and Department of Public Health, Environmental, The Supplementary Material for this article can be found and Social Determinants of Health of the World Health online at: https://www.frontiersin.org/articles/10.3389/fpubh. Organization (WHO). 2021.649447/full#supplementary-material REFERENCES 27 August 2008). Available online at: https://www.who.int/publications/i/ item/WHO-IER-CSDH-08.1 (accessed on February 19, 2020). 1. 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