Rapid Assessment of Avoidable Blindness (RAAB)

What is RAAB?

RAAB is a well-established population-based eye health survey. It assesses the prevalence and causes of vision impairment and blindness among people aged 50 years and older, as well as reporting priority eye care service indicators. It provides locally-relevant data and is used by both governments and non-governmental eye health service providers at national and sub-national levels.

Supporting evidence-based eye care planning, service monitoring and evaluation, RAAB is an important tool in achieving the global eye health priorities set out by the World Health Organization’s World Report on Vision, and the recommendations of the recent Lancet Global Health Commission on Global Eye Health.

RAAB surveys provide the majority of data used to estimate the global and regional prevalence and causes of vision impairment, as well as data which is vital for tracking progress towards universal health coverage. Find out more about RAAB’s uses and impact in our infographic here and the video above.

The methodology has been used to complete nearly 400 surveys of vision impairment and blindness in over 80 countries since 2000, including over 1m participants. RAAB data are collated and displayed on the RAAB website.

RAAB is rapid because it uses simplified examination techniques and requires a small sample size (due to only including examination of people aged 50+).

The main aims of RAAB are to:

• Estimate the prevalence and causes of blindness and vision impairment in the population 50+ in a given area
• Report the effective coverage and visual acuity outcomes of cataract surgical services in people aged 50+
• Report the effective coverage of refractive error services in people aged 50+
• Report barriers to cataract surgical services and near vision spectacles in people aged 50+

Using sound epidemiological methods, these data are then used to design and evaluate eye care programmes in the surveyed area.

RAAB was originally designed for use at the district level but is equally as valuable for reporting national level estimates.

What is the impact of RAAB?

RAAB is integral to ensuring the success of efforts to reduce global eye health:

• The data allows governments and NGOs to plan and evaluate locally-relevant eye health programmes
• RAAB provides much of the data used to estimate global and regional prevalence and causes of vision impairment. RAAB surveys contributed 46% of data for vision impairment and 61% of data for the causes of vision impairment to the 2021 Global Burden of Disease Studies (1,2) for vision impairment. This data informs the IAPB Vision Atlas and has a direct impact on policy, for instance informing the first United Nations’ resolution on vision
• RAAB generates key data to track progress towards WHO global eye health targets: eREC and eCSC. RAAB data was instrumental in establishing a baseline for the targets (100% of eCSC data sources and 87% of eREC sources were from RAAB). RAAB is now being used to measure progress towards the targets

Learn more about the impact of RAAB through this infographic.

RAAB7: the next generation of RAAB

RAAB has been developed iteratively since the early 2000s. The 7th generation of RAAB – RAAB7, launched December 2021, is a joint project between ICEH and Peek Vision. RAAB7 fully digitises the RAAB workflow, delivered on the Peek platform.  It further enhances RAAB’s ability to support eye health planning and includes several new features that deliver higher integrity data such as live data monitoring.

In addition, RAAB7 contains new modules developed to maximise the utility of RAAB in eye health planning.

ICEH have led the research and development of new inputs and outputs for RAAB7, maximising its value as a service tool and generating data aligned to WHO priorities. To date this includes the launch of disability, mental health and socioeconomic status modules and new core near vision content. Other new areas are being piloted that will increase RAAB’s capacity for comprehensive data, such as health economics and health systems.

Acknowledgements

Since its inception more than two decades ago, the Rapid Assessment of Avoidable Blindness has received funding support from many donors including ourselves (ICEH), CBM, the Danish International Development Agency (Danida), Fight for Sight, The Fred Hollows Foundation, the Indigo Trust, Orbis, Peek Vision, The Queen Elizabeth Diamond Jubilee Trust, Roche, Sightsavers and the World Health Organization.

RAAB7 was developed in consultation with a steering group made up of representatives from IAPB, the Vision Loss Expert Group (VLEG), the Vision Catalyst Fund and major eye health non-governmental organisations including CBM, The Fred Hollows Foundation and Sightsavers. Dr Hans Limburg, who first developed the RAAB methodology, remains an active member of the steering group, along with several senior RAAB Trainers. The steering group’s valuable input has helped shape RAAB7 to best serve the sector.

Find out more

Find out more at raab.world or contact the RAAB team on enquiries@raab.world for more information.