Importance of data in disability

In this article we interview Islay Mactaggart who highlights the importance of collecting data and informs on currents initiatives to increase the availability of data disaggregated by disability.

Why is improved data and statistics on disability so important?

The Millennium Development Goals were silent on disability, which has led many to believe that this effectively excluded people with disabilities from fifteen years of International Development, widening the gap between them and people without disabilities. Data on disability was also excludedfrom the Millennium agenda, creating a vacuum of evidence and further marginalising people with disabilities from development.

In contrast, the focus of the newly agreed 2030 Agenda for Sustainable Development is on “inclusive development” that leaves no one behind. To monitor this, we must ensure that robust, reliable and comparable data on disability is included in all reporting on achievements towards the goals. Only by collecting data on whether or not people with disabilities are being included in international development and social progress can we ensure their full and equal participation on an equal basis with others, as per the United Nations Convention on the Rights of People with Disabilities(UNCRPD).

What are current initiatives to collect data on disability?

Several landmark initiatives have not only improved and simplified the methodologies available to collect data on disability, but also mandated its collection.

Firstly, Article 31 of the UN CRPD commands all parties to the convention to collect and disseminate data on disability to formulate, implement and monitor policies in relation to the convention. Secondly, Goal 17.18 of the 2030 Agenda outlines the need to support capacity-building to increase availability of data disaggregated by disability and other characteristics.

This legislation and documentation is supported by international initiatives to promote comparable data collection on disability. The United Nations Statistical Division’s Washington Group on Disability Statistics have developed and extensively tested a short set of six self-reported questions on functioning that have been endorsed by multiple stakeholders, including UN Enable, the Australian Department of Foreign Affairs and Trade, the UK Department for International Development and multiple disability NGO and DPO groups. The use of one tool in multiple countries and over time will drastically improve the comparability and reliability of disability data. 

A new Global Network on Monitoring and Evaluation for Disability-inclusive Development has also been established to bring together these stakeholders and establish a basis for monitoring and evaluating a disability-inclusive 2030 Agenda. This Network will help advance the advocacy around both the importance and feasibility of collecting disability statistics globally.

What are the main challenges to get there?

Whilst The Washington Group Questions (WGQ) have now been agreed as an international standard by global stakeholders as the preferred data collection methodology on disability, there is limited capacity, especially at the programme level, to collect and analyse data for monitoring and evaluation without support. 

Moreover, it is important that the WGQ are understood by users in terms of what they are, and are not. The key strength of the WGQs is their ease of use, replicability and thus comparability. However in isolation, they provide limited data on other key components of disability – including participation restrictions or impairments. It is imperative that whilst the Washington Group Questions are considered the common denominator for all data on disability, that stakeholders wishing to identify and mitigate barriers and facilitators to participation, or to understand service needs related to impairments, are aware of the need to supplement Washington Group data with additional tools.

What can CBM do to support and promote this?

As a leading International NGO working with people with disabilities globally, CBM can promote and endorse the use of the Washington Group Questions to collect data within all CBM programmes. This data is not only useful for monitoring and evaluation at the programme level, but helps build much needed evidence on the situation of people with disabilities. 

In addition, CBM can also engage other stakeholders in addressing their objectives in collecting disability data and use these to define whether or not supplementary tools to collect data on participation or impairments is necessary.


Islay Mactaggart is a Research Fellow in Disability and Global Health at the International Centre for Evidence in Disability (ICED) at LSHTM. Islay’s core research focus is on quantitative methodologies for measuring both the prevalence and the impact of disability in surveys and programs, with an emphasis on the development of modular mobile data collection and analysis tools.