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lang: en
title: Scoping review on 'what works'
subtitle: Addressing inequalities in the World of Work
---

```{python}
from pathlib import Path
data_dir=Path("./02-data")
```

# Introduction

This section will introduce the reader to the concern of inequality in the World of Work (WoW),
and present a discussion on why policy interventions are needed to address these disparities.

# Labour market policies: concepts, functions, typologies and actors

This section will present a typology of policies that directly or indirectly tackle inequalities in the WoW both within the labour market and outside this domain (e.g. education policy).
In order to define the typology of policy areas,
it will be critical to review previous ILO work, in particular de documents outlined by the ToR.
Based on this typology, we will then develop a theory of change to depict policy objectives, components, inputs and functions of distinct types of interventions outlined in the typology.
The section will also identify the theoretical mechanisms and channels through which policies are expected to impact inequalities in forms of work and labour market outcomes.

The ILO has a policy approach to reducing inequalities in the world of work segmented into five major focus areas:
employment creation, access to education, labour rights protection, formalization, gender equality and diversity, and social protection [@ILO2022b].
Each of these areas in turn rests on a variety of more specific emphases which further describe the potential implemented policy measures.

## Policy areas

The ILO has a policy approach to reducing inequalities in the world of work segmented into five major focus areas: employment creation, access to education, labour rights protection, formalization, gender equality and diversity, and social protection.
Each of these areas in turn rests on a variety of more specific emphases which further describe the potential implemented policy measures.
An exemplary typology of general policy area, related specified policy focus and related focus if any can be found in @tbl-policy-areas.

| area of policy           | focus                                              | related                          |
| ---                      | ----                                               | ----                             |
| employment creation      | pro-employment framework                           |                                  |
|                          | gender-transformative framework                    |                                  |
|                          | promotion of business sustainability               | productivity increases           |
|                          |                                                    | reduction in productivity gaps   |
|                          | promotion of digital infrastructure                | technology for decent work       |
|                          |                                                    | reducing digital divide          |
| access to education      | quality of education/training/skills development   | green transition                 |
|                          | relevance of education/training/skills development | digital transition               |
|                          | gender-transformative career guidance              |                                  |
|                          | improvements of public services/social protection  |                                  |
|                          | work-life balance                                  | juggle paid work and family care |
|                          | targeted support for disadvantaged groups          | targeted education               |
| labour rights protection | promotion of rights for all workers                | collective bargaining systems    |
|                          | minimum wage                                       |                                  |
|                          | inclusive labour market institutions               |                                  |
|                          | equal pay for work of equal value                  |                                  |
|                          | wage transparency                                  |                                  |
| formalization            | equality-driven approach to formalization          | gender-responsive                |
|                          | increase decent work in formal economy             | country-tailored                 |
|                          | absorb informal workers / economic units           | comprehensive                    |
|                          |                                                    | non-discriminatory               |
| gender equality          | removal of discriminatory practice                 | removal of stereotypes           |
| diversity                | promotion of equality of treatment                 | removal of discriminatory law    |
|                          | promotion of equality of opportunity               |                                  |
|                          | data collection improvements                       | gender-focus                     |
|                          | occupational gender segregation                    | age-focus                        |
|                          | unequal pay for work of equal value                | disability-focus                 |
|                          | gender-based violence                              | race-focus                       |
|                          | gender-based harassment                            | ethnicity-focus                  |
|                          | gender unequal division of unpaid care work        | migrant status-focus             |
| social protection        | extend reach of social protection schemes          |                                  |
|                          | reach those not adequately protected               |                                  |
|                          | ensure access to social protection                 | comprehensive social protection  |
|                          |                                                    | adequate social protection       |
|                          |                                                    | sustainable social protection    |

: ILO focus areas for inequality reduction {#tbl-policy-areas}

Source: Authors' elaboration based on @ILO2022b.

## The world of work

These policy areas and their respective focus perspectives are based in the conceptual understanding of the world of work, following the definition of work being "any activity performed by persons of any sex and age to produce goods or to provide services for use by others or for own use" [@ILO2013, p.2].
This is the broader understanding of work which specifically separates itself from the more narrow conception of those in employment who are "of working age [and] who, during a reference period, were engaged in any activity to produce goods or provide services for pay or profit" [@ILO2013].
The key concepts for this differentiation are founded on an understanding of the production of goods or provision of services, as well as the distinctions between use by others for ultimate own-use and that of working for pay and/or profit – that is, as part of a market transaction in exchange for remuneration or in the form of profits derived from the goods or services.

Whether these services or goods are produced in what is defined as the informal economy, the formal economy or under informal employment outside the informal sector is, for the general encapsulation of no importance – they occur in the world of work.
Here, conceptually, it should be captured under one of the five mutually exclusive forms of work understood as: own-use production work, performing "any activity to produce goods or provide services for own final use" [@ILO2013, p.5]; employment work comprising those performing work for others in exchange for pay or profit introduced above; unpaid trainee work, performing "any unpaid activity to produce goods or provide services […] to acquire workplace experience or skills" [@ILO2013, p.7]; and volunteer work, that being "any unpaid, non-compulsory activity to produce goods or provide services for others" [@ILO2013, p.8].

Any activity falling under work as defined above on the one hand, but not under any of these forms of work on the other, is instead designated as other work activities in the following considerations. The key concepts between these categories come down to a varying intensity of participation, the distinction of working for pay and/or profit mentioned above, whether it is for ultimate own-use or the use by others, and its compulsory nature.

## Inequalities in the world of work

Inequalities in the world of work have to be fundamentally conceptualized along two axes: On the one hand, vertical inequality captures the "income inequality between all households in a country" [@ILO2021].
Measurements of vertical inequalities is a perspective which focuses primarily on incomes as data, with debate of top income percentiles versus the remaining body of people often posing the primary area of debate [@ILO2021a].
Horizontal inequalities, on the other hand, occur when "some groups within the population find themselves disadvantaged and discriminated against on the basis of their visible identity, for example their gender, colour or beliefs, among others" [@ILO2021a].

Importantly, these inequalities do not act in a vacuum but create an interplay through overlaps and accumulations which take on their own driving dynamics for people belonging to multiple disadvantaged groups, captured in the idea of inequality’s intersectionality [@ILO2022b].
Here, especially horizontal inequalities may be hard to disentangle for impact finding, an important aspect of effective rigorous analysis in quantitative studies.

Thus, for a study on inequalities, or in turn a study on policies aimed at reducing inequalities in the world of work to be one of rigorous analysis, it must clearly define the type of policy taken as its object of analysis (its independent variable) as well as the types of inequalities targeted for reduction through the respective policy and measured as channels of impact.
Ultimately, then, the individual outcome measures need to be clearly specified and disentangled, most clearly reflecting in labour market outcome measures (dependent variables).
Only then can the targeted inequality be delineated as a clear channel.

In targeting an increase in equality, there are then two approaches to take: either levelling the playing field so that characteristics beyond an individual’s control can not influence their future perspectives, nor limit the potential of the powers they possess, through achieving equality of opportunity; or strive for an equality of outcomes, in factual observed resulting (in-)equalities.
As the ILO established, such a focus on equality of outcomes can be of great importance since "high levels of inequality today tend to reduce social mobility tomorrow" [@ILO2021a], making it that much more difficult to ultimately ensure equality of opportunity for following generation.
The key concepts here are thus the distinction of within-group and between-group inequalities, their overlapping characteristics, as well as policies enabling an equality of opportunity or of outcome.

Income inequality is still the primary lens of inequality that many approaches target, as well as the main focus point of many inequality measurements such as the Gini coefficient or ratios such as the Palma ratio [@DFI2023].
Following the ILO, "labour income is the main source of income for most households in the world [thus] unequal access to work and working poverty are major drivers of inequalities" [@ILO2021].
Income inequality, here, can be affected by a wide set of factors: status in employment, forms of work, the sector of activity, the respective occupation, type of enterprise, type of contract for those in waged work, and the status of formality among others [@ILO2019].
Income inequality should also not be seen as separate from, nor standing above, other inequalities, but closely linked to other inequalities.
As the ILO states, "income inequality, inequality of employment outcomes more generally and inequality of opportunities are intimately related" [@ILO2022b].
At the same time the exact linkages of these factors remain under-analysed, which is the reason why the channels of inequalities and the policies to reduce them will pose a fruitful space of analysis for this research.

While income inequality holds a primary position of importance for many analyses from a perspective of quantity, it should not be understood as carrying more importance qualitatively for itself compared to other inequalities but rather be understood "like a prism, which reveals many other forms of inequality, including those generated in the world of work" [@ILO2021a, p. 13].
It is the primary measure of vertical inequality, however, with other inequalities describing primarily the concept of horizontal inequality.

Here, of primary focus for the ILO, and many studies on inequality in the world of work, is gender inequality.
It describes the inequalities that arise because of an individual’s gender.
Generally, while the type and extend of other inequalities does vary substantially by global location and country, "gender inequalities, despite some progress over the past decades, remain persistent and pervasive" [@ILO2021].

Following a report on the gendered make-up of work globally, women are making up a larger part of those in underemployment, they primarily make up the service sector – a rising trend – while suffering a persistently substantial wage gap, tend to work shorter hours in employment but in turn have longer working days when including unpaid work, as well as contributing disproportionally to family work [@ILO2016].
The domestic area of work is also dominated by women, who make up 76.2 per cent of it, in addition to domestic work being overwhelmingly informal labour globally [@ILO2023a].

These inequalities in the world of work in turn also reflect in women being hindered in accessing adequate education, training, as well as the possibility for lifelong learning, and furthermore access to quality jobs, housing, mobility, capital, land, and adequate social protection – disparities which, on the basis of deeply rooted inequalities of gender roles, education and places of residence remain largely static if not on the rise.
These channels and outcomes, viewed intersectionally, must thus represent the primary lens through which to disentangle the gender inequality in the world of work today.

There are additional socio-demographic inequalities beyond gender which are based on the innate, most often visible, identification of a person.
These are made up of, though not limited to, ethnic and racial inequalities, those based on religion and beliefs, based on a person’s status as a migrant, a person’s age, sex, or disabilities [@ILO2021a].
For example, young people generally fare significantly worse in labour markets shown through outcomes such as a higher incidence of temporary employment throughout youth and the young labour force [@ILO2023b; @ILO2019].
As a report on the global conditions of work established, over "7% of workers felt they had been discriminated against in the 12 months prior to the survey on grounds of sex, race, religion, age, nationality, disability or sexual orientation" [@ILO2019] in the EU alone, making socio-demographic inequalities a prevalent and important to tackle angle of horizontal inequality.
Here, it will be especially important to correctly disentangle individual sources or contributing characteristics from each other in finding their linkages to relevant outcomes.

Another form of inequality are spatial inequalities, those that arise because of an individual’s location relative to other.
These inequalities exist primarily between different regions of a country: those between urbanity and rurality or more peripheral areas, but also between richer and poorer regions and, as the ILO established, can even lead to a ‘growing sense of fractured societies’ [@ILO2021].
One of the channels this can manifest itself is through an unequal access to decent work opportunities or economic opportunities more generally, an unequal access to financial resources, quality public services or even overall access to an essential social service infrastructure and digital infrastructure, as well as quality access to education or relevant training.
For spatial inequalities it will be especially important to take note of locally bound differences versus more generalizable results, with the dimensions and contributing factors to its outcomes potentially varying widely between different geographies and national contexts.

In mentioning unequal access to quality education or public infrastructure another important dimension of inequalities becomes highlighted: the dimension of pre-existing inequalities, that is, inequalities which exist prior to an individual’s interaction with the labour market and, though closely intertwined with socio-demographic inequalities, will prove useful to analytically differentiate between.
A differentiation which becomes especially important with a view on the inter-generational effects of inequality, highlighted in recognizing the difference between equality of opportunity and outcome.
The level of education, an individual’s poverty, productivity on the labour market and similar inequalities in opportunities are often the result of long-running pre-existing inequalities such as unequal access to health services, education, lacking property rights or clear ownership of assets, the lack of formal recognition as an individual, no access to formal banking [@ILO2021a].
Understanding such channels becomes difficult if not taking pre-existing inequalities into account as a separate category of inequality and long-term impacting channel.

Addressing these inequalities, in turn, is just as important to reducing inequalities within the labour market (as well as beyond) since they do play such a role for intergenerational social mobility and their impacts can be seen, once again, reflecting in the prism of subsequent income inequality.
For pre-existing inequalities, it will be especially important to understand the often delayed and more opaque nature of the roots of many outcomes, with channel being more difficult to identify and clearly label – especially in an intersectional context.

## Existing reviews

These five dimensions of inequalities – income inequality, gender inequality, socio-demographic inequality, spatial inequality and pre-existing inequalities – will thus provide the categorical anchors along which the reviewed studies will be analysed for their policy effects, each with a slightly different focus in linkages between inequality, policy and outcome.
Aside from the general typology by the ILO introduced above, there are a variety of differing approaches to the interplay of inequalities and outcomes.

<!-- income, spatial, pre-existing -->
In a multi-disciplinary systematic review of the association between a person's income, their employment and poverty in an urban environment, @Perez2022 find that employment plays a significant role in the poverty of urban residents, with primary barriers identified as lack of access to public transport, geographical segregation, labour informality and inadequate human capital.
Many of their investigated barriers can be mapped onto channels of inequality:
gender inequality's impact, through traditional gender roles and lack of empowerment, a lack of childcare possibilities, or unequal proportions of domestic work;
spatial inequality, through residential segregation or discrimination, lack of access to transportation, and a limited access to work;
as well as pre-existing inequalities, here defined as the inter-generational persistence of poverty, larger household sizes, and its possible negative impacts on human capital.
They also identify potential policy interventions to be applied to counteract these inequalities:
credit programs, institutional support for childcare, guaranteed minimum income/universal basic income or the provision of living wages, commuting subsidies, and housing mobility programs.

<!-- gender -->
@Zeinali2021, in undertaking a systematic review of female leadership in the health-sector in low- and middle-income countries, take an intersectional approach and focus on the main barriers at the intersection of gender and social identity.
Here, they find that the main barriers limiting women's access to career development resources can be reduced access to mentorship and sponsorship opportunities, as well as a reduced recognition, respect, and impression of value at work for women in leadership positions.
The main channels of inequalities entrenching these barriers identified were the increased likelihood for women to take on the 'dual burdens' of professional work and childcare or domestic work, as well as biased views of the effectiveness of men's over women's leadership styles.

<!-- policy interv -->
Looking strictly at the impact of basic income interventions on labour market, health, educational, housing and other outcomes, @Pinto2021 find that, while workforce participation is the primary outcome in most studies, the evaluations have shifted over time to include a wider array of outcomes, perhaps reflecting an understanding of lower health and social care spending offsetting some of the basic income investments.
Most of the studies investigating basic income perspectives focus on advanced economies such as the US.

<!-- gender -->
@Finlay2021 looks at the effects of female women's reproductive health on female labour force participation, especially career advancement, job quality and hours worked, to find a variety of responses differing between low-income, middle-income and high-income countries.
The main findings are that in low-income countries because of the prevalence of informal work, women are forced to adopt individual strategies of balancing child rearing and labour force participation through job type selection, reliance on other women in the household for child care, or birth spacing.
In middle-income countries, women have to juggle child rearing and labour force participation with an overall income inequality; here, early childbearing or lone motherhood especially can perpetuate poverty.
In high-income countries, social protection policies can assist in balancing child rearing and work but many underlying issues of gender inequality remain.
Throughout all countries, childbearing significantly interrupts career advancement.

<!-- gender/pre-existing -->
@Chaudhuri2021 conduct a systematic review to look at coping strategies and the effects of food insecurity, often through poverty, on social and health outcomes for women and children.
They find that one of the primary non-food coping strategies for women is to look for outdoor employment, mostly farm work, which can in turn lead to what the authors argue as *time* poverty when their time for childcare or personal nutrition is now cut short.
This in turn can, in combination with food-based coping strategies such as food rationing (in size or frequency), nutritional switches or food sharing, lead to negative health outcomes for children including disrupted socio-cognitive development as well as coping through dropping out of school, thereby furthering the rift of pre-existing inequalities.

<!-- gender -->
@Chang2021 use a qualitative systematic review to look at the linkages of breast-feeding and returning to paid employment for women and identify multiple barriers provided through inequalities discouraging continued breast-feeding after return to employment --- an experience often experienced as physically and emotionally difficult and potentially providing a barrier to full labour force participation.
Aside from individual motivation and support from employers, colleagues, and family members, women highlighted the importance of having workplace legilsation in place to facilitate breast-feeding during employment, as well as access to convenient child care.
The review concludes indicating remaining gender and employment inequalities in accessing and receiving the support needed: gender role expectations viewing women as responsible for domestic work or childcare, with shorter maternity leave further discouraging breast-feeding especially of women not in managerial roles.

<!-- disability -->
Undertaking a systematic review to find the effects of brain tumors in individuals on their labour market outcomes, @Silvaggi2020 find an impact of neuropsychological functioning on work productivity, issues for their process of returning to work, and often an exit from employment (job loss) for long-term survivors of brain tumors.
While the channels are primarily viewed as stemming from the high short-term mortality and depressive symptoms or cognitive deficits, environmental barriers are identified as one channel as well, with the review ending in the policy recommendation of increased vocational rehabilitation for affected persons.

<!-- basic income -->
@dePaz-Banez2020 use a systematic review of empirical studies to look at the effects of universal basic income on labour supply to find that, with no evidence of significant reductions in labour supply, instead the labour supply would increase globally among adults, men, women, young and old.
The insignificant reductions they found they assumed functional, since they were in the categories of: children, elderly, sick, people with disabilities, women with young children, young people continuing their studies and were offset by the otherwise increased supply.

<!-- disabilities, gender -->
Looking at the impact of gender on the employment outcomes for young disabled adults, @Lindsay2018a find that while youth with disabilities are half as likely to be employed, gender inequalities may play a compounding role with men being more likely to be in employment than women, working longer hours and having higher wages.
The identified channels here are different social supports, gender role expectations, as well as women's lower job expectations and overprotection from parents or guardians discouraging their independence.

<!-- gender -->
@Kumari2018 look at the relationship of both economic growth and gender disparity on the labour supply in investigating their effects on female work participation.
<!-- TODO explain U-shape -->
They see a U-shaped participation rate and some evidence of cross-sector gender pay disparity which is affected by demographic factors such as migration, marriage, child care and fertility, as well as economic factors such as per capita income, unemployment, infrastructure and the prevalence of non-farm jobs.
Ultimately, they argue that the labour supply inequalities are based on inequality between the sexes and, while regulatory measures such as adequate family and childcare policies, tax regimes and the presence of subsidized healthcare help, changes to the female labour force participation fundamentally require the replacement of such a traditional value system itself.

<!-- income -->
While undertaking a systematic review concerning the effects of adopting technology on employment in LICs or LMICs, @Ugur2017 find when adoption favours product innovation positive effects are somewhat likely.
They also find, however, that existing income inequalities can make the possible positive effects of its adoption more ambiguous and may in turn widen the rift of demand for skilled versus unskilled labour.
Lastly, policies favouring green transition technologies may in turn reduce income inequality, providing another possible linkage.

<!-- disability -->
@Lettieri2017 find that hiding mental illness is one of the primary strategies for improved employment outcomes in a meta-review looking at barriers to labour market inclusion for people mental disabilities.
This act of concealment of identity and self-stigmatization can seem necessary, they argue, due to the channels of workplace prejudices, perceiving them missing skills, as dangerous or unpredictable, or seeing the act of their hiring as charity due to expectations of lower productivity; but also due to discriminatory hiring practices and pre-existing inequalities leading to them being lower-skilled individuals due to prior discrimination, cultural and social barriers to training and work inclusion.
Here, relevant policies include interventions of supported employment (removing an environmental barrier), cognitive behavioural or computer-assisted therapies (cognitive barrier) or vocational rehabilitation programmes (human capital).

<!-- gender -->
@Taukobong2016 review various dimensions of female empowerment and their effects on a variety of health and development outcomes, including the access and use of financial services for the poor.
They find that, aside from gender inequalities being both highly contextual and intersectional, especially the channels of control over one's income, assets, resources, having decision-making power and individual education affected these outcomes across all dimensions, reflecting their position as channels of gender inequality.
Additionally, personal mobility, safety and equitable interpersonal relationships are associated with some health and family planning outcomes.
Ultimately, the review shows that due to the contextual nature, interventions need to identify the variations of inequality at their start, see where inequalities exist, overlap and work as barriers for an effective implementation.

<!-- disability -->
@Ruhindwa2016 review a variety of barriers to adequate workforce inclusion for people with disabilities, proposing an inclusive approach in which the individual is given space to take ownership of the solutions addressing challenges experienced in the employment sector.
Similarly, they view hiring discrimination and workplace stigmatization as the largest channels through which inequalities of disability manifest themselves.
They see especially employment support practices, with focus on enabling this, as relevant policy strategies, as well as national campaigns to ease disclosing one's disability in the labour market.

<!-- disability, gender, age -->
In looking at the various dimensions affecting the labour market outcomes of supported employment interventions for people with disabilities, @Kirsh2016 finds that most literature still only regards the overall efficacy of the interventions without taking into account compounding intersectional characteristics.
They find that generally men are more likely to find employment through the intervention, possibly resting on current programmes focus on manual labour, as well as younger people generally finding better employment.
This highlights the intersectional nature of inequalities between disability, gender and age.
One relevant policy they see is that of vocational rehabilitation.

<!-- disability -->
@Hastbacka2016 undertake a scoping review to find the linkages between societal participation and people with disabilities, looking at specific interventions for the identity of participants, types of participation analysed, and channels of effect.
They see most literature focusing on labour market participation and viewing disabled people as coherent group instead of intersectional.
The main channels of inequality providing barriers they identify are financial factors, attitudes of discrimination, health issues and unemployment, while the main driving mechanisms identified are legislation and disability policies, as well as support from people in close contact with disabled people and attitudes in society and the hiring process.

<!-- disability -->
In a systematic review looking at the effectiveness of workplace accommodations on employment and return to work, @Nevala2015 few studies with rigorous design leading to conclusive evidence.
They do find moderate evidence that employment in disability can be increased through workplace accommodations such as vocational counselling or guidance, education, self-advocacy, positive perception and help by others.
There is also low evidence for return to work being increased by education, work aids and techniques and cooperation between employers and other professionals (such as occupational health care, or service providers).

# Scoping Review methodology

This section will discuss the systematic scoping review methodology that is proposed to conduct the review of the literature on policy interventions that are expected to address inequalities in forms of work and labour market outcomes.
Unlike purely systematic reviews, which typically focus on specific policy questions and interventions, systematic scoping reviews focus on a wider spectrum of policies, where different study designs and research questions can be investigated.
Since scoping reviews allow both broad and in-depth analyses, they are the most appropriate rigorous method to make a synthesis of the current evidence in this area [@Arksey2005].

```{python}
#| echo: false
# load and parse overall bibtex sample
import bibtexparser

bib_string=""
for partial_bib in data_dir.joinpath("raw/wos").glob("*.bib"):
    with open(partial_bib) as f:
        bib_string+="\n".join(f.readlines())
sample = bibtexparser.parse_string(bib_string)
```

The scoping review allows broad focus to be given to a subject for which no unified path with clear edges has been laid out yet by prior reviews, as remains the case with policies targeting inequalities in the world of work.
It does so through a breadth-first approach through a search protocol which favours working through a large body of literature to subsequently move toward a depth-favouring approach once the literature has been sufficiently delimited.
Its purpose, clearly mapping a body of literature on a (broad) topic area, is thereby useful on its own or in combination with a systematic approach [@Arksey2005].
With an increasingly adopted approach in recent years, with rigorous dichotomy of inclusion and exclusion criteria it provides a way of charting the relevance of literature related to its overall body that strives to be free of influencing biases which could affect the skew of the resulting literature sample [@Pham2014].

<!-- TODO need correct above definitions -->
The search protocol will be carried out based on the typology of policies as well as the possible combination of definitions and outcomes in the WoW.
For each dimension of definitions, a cluster containing possible utilized terms will be created, that is for: definitions of work and labour, forms of work, definitions of inequality, forms of vertical and forms of horizontal inequalities, labour market outcomes, and definitions of policy.
Each of the clusters contains synonymous terms as well as term-adjacent phrase combinations which are in turn used to refine or broaden the search scope to best encapsulate each respective cluster, based on the above definitions.

<!-- TODO Why WOS database? -->
The search protocol then follows a three-staged process of execution: identification, screening and extraction.
First, in identification, the above categorizations are combined through Boolean operators to conduct a search through the database repository Web of Science.
The search itself is conducted with English-language search queries only.
<!-- TODO will we be using gray lit? -->
Relevant results are then complemented through the adoption of a ‘snowballing’ technique, which analyses an array of published reviews for their reference lists to find cross-references of potentially missing literature.

```{python}
#| echo: false
from IPython.core.display import Markdown as md

sample_size = len(sample.entries)
md(f"""
The exploratory execution of queries results in an initial sample of {sample_size} studies after the identification process.
The majority of studies result from the ‘income’ inequality cluster of the Boolean search, with horizontal cluster terms used often but rarely on their own.
""")
```

Second, in screening, duplicate results are removed and the resulting literature sample is sorted based on a variety of excluding characteristics based on: language, title, abstract, full text and literature supersession through newer publications.
Properties in these characteristics are used to assess an individual study on its suitability for further review.

Narrowing criteria are applied to restrict the sample to studies looking at i) the effects of individual evidence-based policy measures or intervention initiatives ii) attempting to address a single or multiple of the defined inequalities in the world of work.
iii) using appropriate quantitative methods to examine the links of intervention and impact on the given inequalities.
The narrowing process makes use of the typology of inequalities, of forms of work, and of policy areas introduced above as its criteria.
An overview of the respective criteria used for inclusion or exclusion can be found in @tbl-inclusion-criteria.

| Parameter   | Inclusion criteria                                                           | Exclusion criteria                                                         |
| ---         | ---                                                                          | ---                                                                        |
| Language    | study written in English                                                     | study not written in English                                               |
| Time frame  | study published in or after 2000                                             | study published before 2000                                                |
| Study type  | primary research, literature review                                          | opinion piece, editorial, commentary, news article                         |
| Study focus | inequality or labour market outcomes as primary outcome (dependent variable) | neither inequality nor labour market outcomes as dependent variable        |
|             | policy measure or strategy as intervention (independent variable)            | no policy measure/strategy as independent variable or relationship unclear |
|             | rigorous quantitative analysis or multi-method approach                      | purely qualitative or no clear description of methodology                  |
|             | specifically relates to some dimension of world of work                      | exists outside world of work for both independent and dependent variables  |
|             | focus on dimension of inequality in analysis                                 | no focus on mention of inequality in analysis                              |

: Study inclusion and exclusion scoping criteria {#tbl-inclusion-criteria}

To facilitate this screening process, a system of keywords is used to tag individual studies in the sample with their reason for exclusion, such as ‘excluded::language’, ‘excluded::title’, ‘excluded::abstract’, ‘excluded::superseded’.
This keyword-based system is equally used to further categorize the sample studies not falling into exclusion criteria, based on primary country of analysis, world region, as well as income level classification.
To that end, a ‘country::’, ‘region::’ and ‘income::’ are used to disambiguate between the respective characteristics, such as ‘region::LAC’ for Latin America and the Caribbean, ‘region::SSA’ for Sub-Saharan Africa; as well as for example ‘income::low-middle’, ‘income::upper-middle’ or ‘income::high’.
These two delineations follow the ILO categorizations on world regions and the country income classifications based on World Bank income groupings [@ILO2022].

Similarly, if a specific type of inequality, or a specific intervention, represents the focus of a study, these will be reflected in the same keyword system, through for example ‘inequality::income’ or ‘inequality::gender’.
The complete process of identification and screening is undertaken with the help of the Zotero reference manager, ultimately leaving only publications which are relevant for final full-text review and analysis.

Last, for extraction, studies are screened for their full-texts, irrelevant studies excluded with ‘excluded::full-text’ as explained above and relevant studies then ingested into the final sample pool.
All relevant information concerning both their major findings and statistical significance are then extracted from the individual studies into a collective results matrix.

The results to be identified in the matrix include a study’s: i) key outcome measures (dependent variables), ii) main findings, iii) main policy interventions (independent variables), iv) study design and sample size, v) dataset and methods of evaluation, vi) direction of relation and level of representativeness, vii) level of statistical significance, viii) main limitations.

# Synthesis of Evidence

This section will present a synthesis of evidence from the scoping review.
The evidence will be presented by type of policies and world regions.
The section will also present a discussion on the implications of the current evidence base for policy and underscore key knowledge gaps.

# Conclusion

The section with conclude with reflections on the implications of findings for policy.

\pagebreak

# References

::: {#refs}
:::

\pagebreak

# Appendix

## Full search query

```sql
TS=
(
    (
        work OR
        labor
    ) AND
    (
        production of goods OR
        provision of services OR
        use by others OR
        own-use OR
        for pay OR
        for profit OR
        remunerated OR
        for wages OR
        waged OR
        for salaries OR
        salaried OR
        for time worked OR
        for work done OR
        profits derived OR
        through market transactions
    )
) AND

TS=
(
    employment OR
    unpaid trainee OR
    volunteer OR
    domestic work OR
    wage-employed OR
    self-employed OR
    formal employment OR
    informal employment OR
    unpaid care work OR
    care work
) AND

TS=(
    intervention OR
    policy OR
    policies OR
    participation OR
    targeting OR
    targeted
) AND

TS=
(
    inequality OR
    inequalities OR
    barriers OR
    advantaged OR
    disadvantaged OR
    discriminated OR
    disparity OR
    disparities
) AND

TS=
(
    income OR
    identity OR
    gender OR
    beliefs OR
    color OR
    racial OR
    ethnic OR
    ethnicity OR
    migrant OR
    nationality OR
    spatial AND
    (
        rural OR
        urban OR
        mega-city OR
        large city OR
        small city OR
        peripheral city
    ) OR
    age AND
    (
        young OR
        youth OR
        old OR
        senior
    ) OR
    disability OR
    health status OR
    education OR
    educational access OR
    social mobility
) AND

TS=(
    employment outcome OR
    labor rights OR
    opportunities between groups OR
    equality of opportunity OR
    equality of outcome OR
    labour market outcome OR
    income OR
    job quality
)
```

\pagebreak
