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Faster, more accurate and more insightful: a closer look at the latest version of the RAAB population-based survey

Published: 08.12.2021
Professor Matthew Burton Director of the International Centre for Eye Health
International Centre for Eye Health
Andrew Bastawrous CEO of Peek Vision and Professor in Global Eye Health at ICEH
Peek Vision

The Rapid Assessment of Avoidable Blindness (RAAB) will be a name that’s familiar to many in the eye health sector. This well-established population-based survey was developed by international eye health expert, Dr Hans Limburg, more than two decades ago. To date, more than 330 RAAB surveys have been conducted in over 80 countries, providing key data for evidence-based eye care planning and service monitoring.

Over the past three years, the International Centre of Eye Health (ICEH) at the London School of Hygiene & Tropical Medicine and Peek Vision have been collaborating to develop a new version of RAAB, called RAAB7, which is delivered digitally using Peek technology. Working closely with Dr Limburg, and with a wider steering group made up of representatives from the global eye health sector, we have developed a tool to meet the sector’s evolving needs, and which enables users to capture the highest-quality eye health planning data possible.

RAAB has been integral in providing data for the eye health field and beyond – data which has contributed to raising the profile of eye health at the national and international level, including in the recent United Nations General Assembly resolution on eye health. This new, updated and digitised tool further develops the potential of RAAB surveys to serve the global community with efficient, high-quality data.

The World Health Assembly recently adopted two eye health indicators as part of the reporting by countries of Universal Health Coverage (UHC): Effective Cataract Surgical Coverage (eCSC) and Effective Refractive Error Coverage (eREC). RAAB7 provides data analysis of both indicators for the effective design and reporting of programmes that leave no one behind.

What are the key features of RAAB7 and how does it differ from the previous versions it replaces?

With RAAB7, data collection is carried out using a mobile app. This eliminates the need for staff to laboriously double enter data from paper forms into a computer database and cross check for errors.

Automating this whole process at the point of data collection reduces data errors, as the app has in-built validation checks. Data errors are flagged at the point of entry, so they can be corrected while the survey participant is still present (previously these errors were only found later, and so were difficult to correct appropriately).

Visual acuity is measured using the integrated clinically-validated Peek Acuity test, rather than paper charts. The survey app also automatically skips questions which are no longer relevant based on a respondent’s answers to the previous ones. Overall, this digital data capture significantly speeds up the survey process.

The new RAAB7 app automatically uploads the data to a secure cloud-based server, resulting in a more efficient and streamlined process. The cloud-based data storage also protects against risk of data loss. Live survey data is displayed for the RAAB project leader on a new RAAB7 web platform, with a dashboard to enable them to track survey progress in real time and respond quickly to any issues that may arise.

The RAAB7 methodology collects data and performs the analysis for both eCSC and eREC –two key indicators for eye health service planning and reporting.

In addition to the existing diabetic retinopathy module, we have added an optional disability module using the Washington Group Short Set, a module endorsed by various United Nations agencies for disaggregation of Sustainable Development Goal indicators.

Data security has been a central priority in this project. All data collected is encrypted and the secure cloud solution operates industry standard security controls and meets strict security and data protection requirements. This ensures RAAB7 and all data processed, is in compliance with the General Data Protection Regulation (GDPR). Since 2018, the GDPR has set the tone internationally for new data protection regulations with many countries broadly aligning their own data laws to the same principles as the GDPR.

As part of the RAAB7 project, a new RAAB website has been launched which replaces the repository established and maintained by Hans Limburg. The new website collates all available historic RAAB data, and will include data from future RAAB7 surveys for users to interrogate. At a minimum, metadata from all surveys will be available on the website. Release of additional, anonymised survey outputs on the website is at the discretion of the RAAB Principal Investigators (PI). We hope PIs will share as much data as they are comfortable with, as doing so will be of huge benefit to the sector to support global analysis and understanding.

RAAB7 has been designed with and for the eye health sector. It is not a profit-making venture. However, in order to contribute towards the costs incurred by Peek and ICEH to support the delivery of a RAAB7 survey, there is a modest technology license and service fee in place for users. All additional ongoing software maintenance costs, as well as the costs associated with further development of the methodology and software, are covered by Peek, ICEH and donors.

A number of organisations have piloted RAAB7 during development, and now it is complete there are 19 new surveys in 12 countries planned for the coming weeks and months. We’re looking forward to seeing the benefits RAAB7 brings to users and to the wider sector. We would like to thank the RAAB steering group for their insightful input and support throughout the project, and especially Dr Hans Limburg for his ongoing support and advice while we have used the latest technology to update and expand this important tool to help reduce vision loss around the world.

For more information and a full list of RAAB7’s enhanced features visit