About this evidence map

The purpose of this evidence map is to provide an overview of the availability of evidence on modern slavery interventions in India, Nepal, Bangladesh and Pakistan.

The evidence map provides an outline of where evidence is concentrated and where it is missing by mapping out existing and ongoing impact evaluations and observational studies exploring different types of modern slavery interventions and outcomes for specific target populations (survivors, employers, landlords, services providers, criminal justice officials) and at different levels (individual, community, state).

The cells of the evidence map contain bubbles of different colours and size. The colours represent the countries to which the studies related. Blue is Bangladesh, yellow is India, red is Nepal and green is Pakistan. The bubble size is proportional to the number of studies reporting those interventions and outcomes. Clicking on a cell gives a list of studies corresponding to the intervention and outcomes for that cell. Clicking on a study in the list will provide publication details and URL to access the study itself.

The evidence map also identifies key ‘gaps’ in evidence, Cells which do not have any bubbles indicate no evidence from impact evaluations or observational research was found relating to that intervention/outcome.

A multi-stage search strategy was followed, comprising electronic searches of academic and non-academic databases and websites, using keywords for intervention studies, evaluations and observational research which included an intervention and regionally focussed systematic reviews published in English between 2008 and 2018. In addition, we collected NGO reports on modern slavery that were consistent with the inclusion and exclusion criteria.

The map includes impact evaluations and observational research which involved an intervention. This map shows the coverage of 116 studies eligible for inclusion.

This map is foremost targeted to DFID and its partners in India, Nepal, Bangladesh and Pakistan to inform evidence-based policy making. We hope that it is also useful to academics and practitioners working to address modern slavery, or in intervention areas or locations described.

A full report outlining how the Evidence Map was developed is available here https://www.heart-resources.org/wp-content/uploads/2018/12/MS-Evidence-Map_Report.pdf. Click here for the full report

Excel based spreadsheet

A static overview of the evidence map setting out the number of studies identified by the systematic searches which addressed each combination of interventions and outputs or outcomes and a visual display of key results presented in the report can be found here. You will find the following tabs at the bottom of the sheet.

1) Database tab:

This contains a list of all of the documents selected from the rigorous review that met the defined inclusion criteria. Further details of the search strategy and inclusion criteria can be found in the main report. The database is searchable by a series of classification types that include: study design; modern slavery type; country; interventions and outcomes.

The filter options can be used to display a list of documents that provide evidence on different criteria. For example, one could search for documents that contain evidence obtained from 'Observational - Qualitative' studies with a thematic focus on 'Child Labour', which contains evidence from 'India' on the intervention type 'Economic interventions', and that comments on the outcome 'Economic factors' at the community level.

To refine the selection of documents displayed, click on the filter button at the top of each searchable column. A box will appear with three options: '(Select All)', 'x', and '(Blanks)'. In order to select only the documents that meet that criterion, all boxes should be unselected by clicking on the box next to '(Select All'). This needs to be followed by selecting 'x', which will bring up a list of documents meeting that criterion. Documents can be searched by combinations of criteria by selecting multiple filters.

To return to the full list, 'unfilter' by clicking on each filter button used and clicking on the '(Select All)' box.

1) Evidence Gap Map tab:

This table shows the number of studies included in this review that addressed each combination of interventions and outcomes. Green cells show where the review found a significant number of studies - darker shades of green indicate more studies found. Red cells highlight evidence gaps - darker shades of red indicate greater evidence gaps. White cells are neutral, representing that there are a fair number of studies for that intervention and outcome.

2) Tabs with charts summarizing evidence, interventions and outcomes:

The final three tabs summarise the type of evidence identified by the mapping. The tab evidence charts displays a summary of the evidence presented in the main report, with sub-totals of the number of studies by study characteristics. The tabs interventions and outcomes show the number of studies by study characteristics (study design; type of modern slavery; publication date) for different types of interventions and outcomes.

Important note regarding the coding of documents

Studies have been included in the database and coded as being related to an outcome if they evaluated the impact of an intervention that was intended to lead towards that outcome, regardless of whether the intervention was successful in its aims or not.


This map was commissioned by the Department for International Development (DFID) and undertaken by the Institute of Development Studies and Oxford Policy Management as part of HEART (Health and Education Advice and Resource Team). HEART is a framework programme supporting the use of evidence and expert advice to underpin development decision-making.

This database was compiled by Charity Jensen, Raudah Yunus, Francis Somerwell, Pauline Oosterhoff & Nicola Pocock