Superdiversity re-imagined: Applying superdiversity theory to research beyond migration studies

Essential elements of superdiversity theory

The inquisitive position adopted by superdiversity theory (Vertovec, 2012) fits with the curiosity stance so long embedded in the sociological tradition (Mills, 1959) and more recent work on innovation in research (Taylor and Coffey, 2008). Superdiversity theory rejects a myopic interrogation of a phenomenon and instead requires a deeper study of the patterns which can be discerned within data, such as the small-group-within-the-big-group patterns that illuminate points of micro diversity within larger populations (Meissner, 2015; Ozkazanc-Pan, 2019). Although the word ‘super-diversity’ suggests something big and voluminous, superdiversity is actually concerned with the micro differences that distinguish one population sub-group from another. The super in superdiversity, it could be suggested, is both its strongly inquisitive stance and also its depth and reach in terms of how it requires the researcher to excavate datasets in order to reveal crucial distinctions in patterned behaviours between sub-groups.

Superdiversity theory has also succeeded in changing how we perceive population diversity in contemporary society, heralding a shift in how we understand the composition of migrant populations (Grzymala-Kazlowska and Phillimore, 2018; Ozkazanc-Pan, 2019). López Narbona (2019) explains how superdiversity encourages us to understand the characteristics and experiences of sub-groups within the larger population. It thus encapsulates and encourages new thinking about old problems, employing technological advances to both make and disseminate discoveries (see for example, Vertovec et al., 2019).

A key element of superdiversity theory is its ability to identify and analyse patterns of sameness or difference within target populations. In this sense, it is a flexible, elastic theory, which requires a level of dexterity on the part of the researcher. Uninterrogated categorisation of variables is rendered research-clumsy because superdiversity has revealed how even small variations within a research population can point to the existence of distinct sub-groups. The limitations of failing to identify distinct sub-groups, and being content to only note that they share some major overarching characteristic such as country of origin, are laid bare by superdiversity as ineffective in determining the relationships between all relevant variables. In superdiversity research failing to identify unifying or distinguishing patterns before classifying individuals into one population group or another is akin to seeing chalk and cheese as essentially similar.

An essential element of superdiversity theory is its focus on differences in populations ascribing importance to understanding how nuanced differences in a population can reveal important information about the existence of different experiences within any particular sub-group. Essentially, superdiversity highlights the limpness of research which homogenises population datasets and fails to take account of the relevance of discernible differences in population characteristics and experiences. It rejects uncritical assumptions of conformity in research populations and the inherent strength of this framework is its commitment to identifying pattern distinctions within large populations. In this sense, superdiversity research is curiosity-driven, positioning it comfortably alongside the enquiring stance intrinsic to the sociological imagination as articulated by the Millsian tradition (Mills, 1959).

In summary, the essential elements of superdiversity identified here include the following:

The question posed in this article is to what extent these essential elements can be usefully applied in research of issues beyond the study of migration-related phenomena. They potentially hold value, it will be argued, in producing new knowledge of other phenomena in society. The next section of this article considers how research on a different topic, namely, mental illness, could be transformed if informed by the essential elements of superdiversity theory. Firstly, a brief overview of the field of mental illness research is provided including reference to some of the tensions which currently surround investigation of this topic.

Paradigms of mental illness

A number of competing paradigms claim to explain the aetiology or causes of mental illness, with the biomedical model currently regarded as the dominant explanatory paradigm. In this model, mental illness is understood to arise from an organic or physiological aetiology, such as genetic predisposition, injury or disease. The biomedical perspective has developed within the period of modernity to become the most embedded explanatory paradigm of mental illness, successfully unseating the established beliefs of previous eras which associated symptoms of mental illness with evil or social deviance (Conrad and Schneider, 1985). In the biomedical paradigm, abnormal symptoms are interpreted as signs of illness, such as brain disease or organic malfunction (Conrad and Schneider, 1985).

Thus, the biomedical perspective has produced important advances in diagnostic and treatment knowledge and is generally portrayed as scientifically progressive (Hyde et al., 2004), partly because it favours positivist methodologies and partly due to the advances in symptom management which it has achieved. While somatic explanations of madness circulated in ancient societies (Eghigian, 2010; Rosen, 1968), the current biomedical model can be traced back to the work of 19th-century physicians such as Emil Kraepelin, who is credited with laying the foundations of the biomedical nosology of mental illness, now a foundational cornerstone of psychiatric theory. Kraepelin is acknowledged for progressing understandings of mental pathology, classifying the symptoms of schizophrenia (he termed it ‘dementia praecox’) (Angst and Marneros, 2001). Contemporaries of Kraepelin included Paul Eugen Bleuler who, building on the work of Kraepelin, first applied the name of schizophrenia to a specific group of symptoms (Maatz and Hoff, 2014). These early attempts at establishing diagnostic criteria laid the foundation for contemporary mental illness symptom classification systems now in widespread use, including the Diagnostic and Statistical Manual of Mental Disorders (DSM V) (American Psychiatric Association, 2013) and the International Classification of Diseases (ICD-10) (WHO, 2016). McCarley et al. (1993) note that Kraepelin was convinced that mental distress had an organic (physiological) basis, although Bleuler remained open to the possibility that psychological and social factors might also contribute to the onset of mental illness. This is perhaps one of the earliest examples of contestation within the discipline of psychiatry and as will be seen, psychiatry, as a body of knowledge, continues to be challenged from a range of critical perspectives.

As noted above, mental illness symptom classification systems are now utilised to interpret symptoms and aid diagnosis. While the different taxonomic systems concur in many respects, they are criticised for not being identical. Critics of the medical model also draw attention to the absence of objective medical tests, such as an x-ray or blood test, which often leaves diagnosis of symptoms relying on observable behaviour and patient self-reports. The lack of objective, diagnostic tests, the existence of different classification systems and the incomplete evidential basis of psychiatric theory raises concern about a lack of cohesion within the medical model (Kirk and Kutchins, 1994; Kutchins and Kirk, 1993; Maynard, 2014; Timimi, 2014). This situation has rendered the biomedical model of mental illness vulnerable to criticisms from a number of quarters, including those which are outlined in summary form below.

The proposition that macro and micro social factors may act as triggers of mental illness has been suggested by adherents of the ‘social model of mental illness’ (Beresford et al., 2016). Some writers (e.g. Read, 2004; Read and Haslam, 2004) question the assumption that mental illness only arises from physiological problems, although they recognise that it may include the experience of physiological symptoms. They accept that physiological problems may be a possible cause of mental illness but reject them as the singular possible cause of mental illness. Furthermore, they are unconvinced by the epistemology underlying the medical model, believing it relies on a contested scientific foundation (Beresford et al., 2016). Apart from the concerns about scientific robustness of current mental illness diagnosis, there are also concerns about the implications which attach to being diagnosed as mentally ill. The WHO (2013) reminds us that applying classifications of mental illness onto individuals can have significant implications for them in terms of how they are viewed by others and dealt with by the rest of society. Davidson et al. (2016: 42) caution that the assignment of mental illness diagnoses can have far-reaching consequences:

We need to understand how ‘experts’ contract the language of mental health and illness and its impact on the everyday lives of clients whose thoughts, behaviour and feelings are interpreted through these discourses.

Indeed, the WHO (2019a) moves beyond a singular explanatory paradigm when it states that the determinants of mental health include a wide range of social, cultural, economic and political factors.

Within the discipline of sociology, further challenges to the biomedical model can be identified. For example, some commentators argue that insufficient attention is paid to the impact of positive or negative social and psychological factors on individual mental health and mental resilience including positive factors such as supportive relationships or positive work environments and negative factors such as childhood abuse, homelessness, domestic violence, relationship difficulties and lack of social capital (Hammersley et al., 2008; Johnstone, 2000, 2011; Kirwan, 2020; McKenzie et al., 2002).

Critical theorists, such as Foucault (1965, 2011 [1954]), have highlighted how the current psychiatric taxonomy of symptoms presupposes rather than confirms the existence of a physiological explanation of mental illness. Varga (2005: 221) discusses the Marxian prediction that in modernity the ‘scientificising’ of the body arises from the capitalist need to control the bodies of workers. A similar teleological viewpoint is progressed by Foucault (2011 [1954]), whose general critique of the medical model of mental illness, and the discipline of psychiatry in particular, positions it as a force of social regulation and surveillance. For Foucault, the pathologising of behaviour, in other words the social construction of madness, functions as a form of control and discipline enacted by psychiatry on behalf of the wider society. Foucault (1977) argues that the function of assessment, he terms it ‘the examination’, is to compare the individual to a set of normative ideals and if they fall short then treatment and/or segregation is prescribed in order to manage the individual’s behaviour or remove them from societal view. In this new regime of discipline, he argues, the function of symptom categorisation and treatment is ‘not to punish less, but to punish better’ (Foucault, 1977: 81–82). The pathologisation of homosexuality, and its historical (now rejected) categorisation as a form of mental illness, is cited by some authors as an example of the social control potential of mental illness labelling. Cotton and Ridings (2011), also Drazenovich (2012), illustrate how the historical pathologisation of homosexuality, as an example of a socially constructed mental disorder, simply transformed or reconstructed the societal attempts to control homosexuality from a form of punishment to a form of treatment.

Rapley et al. (2011: 1) describe the current systems of mental illness classification as an attempt at ‘codifying human suffering into disease-like categories’. They criticise the ‘positivist psychiatric project’ (Rapley et al., 2011: 1), suggesting instead that the medicalisation of mental distress has been to the disadvantage of society in general. Pickersgill (2013) critiqued the meta-narratives of neuroscience referring to Rose’s (2007) observation that we have become ‘neurochemical selves’, as we invoke brain-based explanations of our feelings and experiences.

However, the various stances within the sociology of mental illness lack agreement and despite the level of criticism directed towards it, the field of medical science continues to hold a hegemonic paradigmatic position and to receive strong societal endorsement and support.

Another source of resistance to the biomedical model has come from within the discipline of psychiatry itself. The literature from the anti-psychiatry movement, and the more recent post-psychiatry movement, is relevant in this regard. Although there are distinctions between these two discourses, there are also wide areas of concurrence in the criticisms which both movements raise against the biomedical model. Szasz (1974) and Laing (1985) express the core concerns of the anti-psychiatry movement regarding the legitimacy of the biomedical model because of what they regard as its weak empirical base. The influence of the anti-psychiatry movement has been all the more forceful because its origins emerged in the writings of practising psychiatrists. Laing (1985) highlights the failure of the medical model to firmly evidence the physiological basis of all mental illness while at the same time continuing to promote the idea that a solid scientific basis exists for the knowledge claims it makes. Furthermore, Laing (1985) and Szasz (1974, 1976) both argue against the ongoing medicalisation of mental distress, because, in their view, the scientific evidence to confirm the efficacy of medical treatments is weak. In particular, they strongly condemn the growth of the global pharmaceutical industry. Laing argues that non-biological factors which may contribute to the onset of mental illness, such as conflictual relational contexts, are too often overlooked or deliberately excluded in biomedical research on the causes of mental illness (see also Laing and Esterson, 1964).

In agreement with the anti-psychiatry discourse, Johnstone (2000: 218) views the weak scientific base of the medical model as problematic and she argues that pharmaceutical treatments ‘probably cause as much disability as they cure’, a theme resonant of Szasz’s (1974) similar criticism. She criticises the continued commitment by the pharmaceutical industry to the development of medicines while simultaneously under-researching the potential of social and psychological interventions. Although, Johnstone (2000) is willing to acknowledge that medicinal treatment provides assistance to some people, she is not convinced that the medical model will, on its own, produce solutions to all the forms of mental illness prevalent in society.

Johnstone (2000, with reference to Boyle, 1990), distinguishes the medicalisation of mental illness from other branches of medicine where more objective evidence underpins symptom classification, diagnosis and treatment. For writers such as Szasz, Laing and the wider anti-psychiatry movement, there is no continued justification for the dominance of the medical model in treatment or research because from their perspectives it over-relies on the claims that at some future point it will identify the causes and find cures for the underlying physical attributes of mental distress.

The post-psychiatry movement, also termed the ‘critical psychiatry movement’ (Double, 2006) or ‘liberatory psychiatry’ (Cohen and Timimi, 2008), makes very similar criticisms of the medical model of mental illness. Like the original anti-psychiatry movement, post-psychiatry literature includes contributions from contemporary, practising psychiatrists. They question whether or not ‘a medicine of the mind can work with the same epistemology as a medicine of the tissues’ (Bracken et al., 2012: 430). Timimi (2014), echoing Laing and Szasz, criticises psychiatric symptom classification systems, believing they lack a rigorous scientific basis.

The post-psychiatry literature accepts that drug therapy may offer relief from distressing symptoms, but emphasises the difference between ‘relief’ and ‘cure’ and points to the fact that as yet, science has not produced a ‘cure’ for mental illness because it has yet to find its root cause (Moncrieff, 2008, as cited in Thomas et al., 2012: 306).

Bracken (2014) positions the propositions of the post-psychiatry movement as a hermeneutic turn through which psychiatry can free itself from reliance on the evidence-based, positivist approach. Therefore, post-psychiatry is not proposing that psychiatry abandon its mission but instead that it should seek a wider theoretical base, moving beyond the medical model, on which to justify its role in the treatment of mental illness (Thomas et al., 2012). The anti-psychiatrists are mainly concerned to expose the inherent contradictions in the medical model of mental illness, whereas the post-psychiatry discourse is concerned to identify and develop an alternative and more justifiable theoretical base for the practice of psychiatry.

A problem for the post-psychiatry movement, as highlighted in a debate piece by Zachar (2012), is that it seeks to shed a biomedical explanation of mental illness but still argue for a key role for psychiatrists. Zachar (2012), himself a psychiatrist, argues that there is no logic in replacing one incomplete paradigm for another, and particularly a paradigm which, in his view, is a less developed one. He criticizes the post-psychiatry discourse for promoting retrograde anti-modernism (he says they are ‘flirting with anti-modernism’), which he believes opens an unsatisfactory vista of treatment based on weak scientific evidence and which is led mainly by what he terms ‘patient preferences’ (Zachar, 2012: 314). In its defence, post-psychiatry argues back that the usefulness of engaging with the subjective realities (phenomenology) of service users is an aspect of treatment which psychiatry should not exclude from its evidence base.

Lastly, in completing this brief overview of different perspectives on mental illness, it is relevant to note that the psychological model of mental illness acknowledges the contribution that a range of factors, internal and external to the individual, can make in the onset of mental illness. In this light, the psychological model regards physiological pathology as one of many potential triggers of mental illness (Bentall et al., 2009). However, it differs from the medical model because it regards non-biological factors as potentially relevant also.

Despite the existence of alternative paradigms, the biomedical model persists as a legitimate and embedded explanatory model of mental illness. To its adherents, the medical model underpins a progressive field of research and to its critics it is a problematic paradigm which lacks a solid knowledge base (Moncrieff, 2011; Whitaker, 2005). As such, the biomedical model of mental illness is a highly contested space and alive with debate. At the same time, other models, such as the social model or the psychological model, have also failed to make research breakthroughs regarding the causes of mental illness, a point of knowledge relevant to the mental health of millions of people worldwide. It is in this research lacuna that this article turns to superdiversity theory to consider if this new research practice has anything to offer the field of mental illness research.

In particular, superdiversity, it is argued here, offers a potentially valuable new framework into the field of mental illness research because it offers a gateway to new forms of transdisciplinary collaboration in an attempt to examine many variables in large datasets from new angles. Additionally, superdiversity theory emphasises the importance of looking widely at all potential variables relevant to the topic being researched while at the same time identifying atomised differences in the target research population as a means to understanding the whole population. Thus, the application of the essential elements of the superdiversity paradigm to the study of mental illness offers a potential disruptive intervention in this field of research primarily because it will be resistant to paradigm silos which fail to accommodate all possible variables and combinations of variables within a diverse study population. Mental illness researchers, informed by superdiversity theory, may be freed to revise their views on how best to advance knowledge on the factors which surround the onset and endurance of different forms of mental illness. Taking each of the essential elements of superdiversity theory identified earlier, the next section of this article contemplates or imagines how a superdiversity theory lens could help deliver innovation in mental illness research.

A foundation of inquisitiveness

Despite an acceptance of the benefits of multidisciplinary care in mental health services, there is a need for increased commitment to cross-paradigmatic research on the causes of and treatments for mental illness. In the absence of strident progress in identifying the causal variables in the onset of mental illness, novelty in research design is precisely what is needed. Shaking mental illness research free from paradigm constraints appears difficult to accomplish but entirely necessary. For example, in a recent, small-scale study with long-term mental health service users (Kirwan, 2017), participant narratives revealed that people who suffer from severe and enduring forms of mental illness can vary in how they explain the aetiology of their symptoms. In that study, participants identified a range of factors which they associated with the onset of their mental illness symptoms included psychological (worry, distress), social (problematic relationships), emotional (trauma, loneliness) or physical (injuries, illness, genetic predisposition). It is suggested here that more research is needed which seeks to calibrate the contribution of different types of factors in the onset of mental illness symptoms.

A focus on searching for groups-within-groups

Population research, in the form associated with superdiversity studies, has the potential to unlock heretofore unknown patterns in populations. Research on mental illness, freed from paradigmatic constraints, has the potential to reveal patterns and factors which have been difficult to previously identify. An added dimension of superdiversity research, already highlighted, is its capacity to identify factors which unite and factors which differentiate segments of wider populations. The potential of applying a superdiversity lens to mental illness research is that research would no longer be confined, and should not be confined, to a narrow set of variables (for example, physical factors) and could then more accurately reveal the myriad of potentially relevant factors found among population groups who experience mental illness.

The employment of cutting edge data analytics

The application of data analytics on a large scale is potentially paradigm-busting in the context of mental illness research and may help open up for discovery previously hidden patterns between different variables. Research studies adopting superdiversity methodologies can be widened beyond a migration focus to include studies which have, as their main concern, the epidemiology of mental illness. It is perhaps premature to speculate on how superdiversity informed research might differ from mental health research in other traditions, but there are some clues in the existing literature. Arnaut (2015), for example, highlights the ability of superdiversity research to accommodate what she terms simultaneity, a process which acknowledges the multidimensionality of individual lives. As noted earlier, the multidimensionality in the lives of people with mental illness is often invisible in research studies where their non-patient roles, such as parent, carer, worker, etc., are often obscured and left unexplored.

Flexibility in managing sameness and difference in a study cohort

The discursive conflicts surrounding the study of mental illness potentially confines research in this field to stay locked within paradigm silos. A superdiversity-informed research agenda could, potentially, help loosen current paradigm constraints and reveal under-recognised patterns related to mental illness in populations and population sub-groups.

A concern to avoid conflation of distinct sub-groups

In the context of disputed theories of mental illness, it is important for research studies to identify accurately how different factors interact with each other. The methodologies used in superdiversity research offer improved precision in this regard.

A commitment to spotlighting diversification in a dataset

Superdiversity as a research model invites complex analysis as a means of identifying differences within populations. A simple example of difference which is difficult to accommodate in current mental illness research is the range of factors which mental health service users regard as relevant to the onset of their mental illness symptoms (Kirwan, 2017). A superdiversity approach can accommodate simultaneous investigation of many variables and it offers a roadmap for mental illness research which seeks to better understand the patterned presence of mental illness experiences in whole populations.