Rapid Assessment of Avoidable Blindness (RAAB)
What is RAAB?
The Rapid Assessment of avoidable blindness (RAAB) is a rapid survey methodology developed at ICEH, and used to complete over 300 surveys of visual impairment and blindness to date.
RAAB is rapid because it uses simplified examination techniques and, because it only includes examination of people 50+, requires a small sample size.
RAAB incorporates a standardised training programme supported by certified RAAB Trainers, mobile data entry with in-built logic, and automated analysis and report generation. RAAB data are collated on the RAAB repository.
The RAAB software package contains Windows software, supporting documentation and training materials.
Currently there are two versions of the RAAB package: RAAB5 and RAAB6. Please read the text below before downloading to ensure you install the version that is best suited to your needs.
RAAB6 is the latest and most complete version of the RAAB software and is at present also used for the report generation in RAAB7, which is under development and undergoing field tests. Visual acuity <6/12 to 6/18 (mild visual impairment) is included, in line with the latest WHO classification in ICD 11. Features in RAAB6 include:
- calculation of the sample size
- random selection of the clusters with a probability proportional to size
- inter-observer variation (IOV) assessment
- data entry with in-built consistency checks
- double data entry validation
- generation of 10 reports through menu system, with 128 tables and 30 graphs
- functional low vision in people aged 50+ with best corrected VA<6/18 to PL+ in the better eye, which cannot be treated anymore
- optional Diabetic Retinopathy module
The download includes the software plus all supporting materials, like a complete manual, survey forms, IOV forms, teaching slides and a spreadsheet to estimate the costs of conducting a RAAB.
In 2015, a mobile (Android)-based data collection app for RAAB6 (mobile RAAB – mRAAB) was developed by ICEH and Peek Vision. mRAAB6 allowed mobile data collection of the RAAB6 data entry form, with data then transferred via USB to a computer and analysed using the standard RAAB6 software. This improved the speed and accuracy of data collection, as well as eliminating the need for manual data entry of survey forms into the RAAB software programme. mRAAB6 can be downloaded from the Play Store and used together with the RAAB6 software above.
RAAB5 is the previous version of the RAAB software, which considers visual acuity of VA<6/18 as normal vision and does not have the category of mild visual impairment, as was used in ICD 10. Except for this, all reports and functions have been updated as in RAAB6. RAAB5 may still be needed for data sets generated in RAAB4.03 and RAAB5, because these older data files cannot be analysed in RAAB6 anymore. But RAAB5 will not be developed any further. Authors: Hans Limburg, [email protected], and Walter Meester. Diabetic Retinopathy module, Sarah Polack
Publisher: International Centre for Eye Health, London School of Hygiene & Tropical Medicine
Published: RAAB6 and RAAB5 latest updates, March 2020.
Download the RAAB packages
RAAB5 (updated March 2020)
English version ZIP (225MB)
Spanish version ZIP (199 MB)
RAAB6 (updated March 2020)
English version ZIP (220 MB)
Spanish version ZIP (219 MB)
RAAB training certification Good planning and organisation are vital for success when carrying out RAAB surveys. We strongly advise you to co-ordinate with a certified RAAB trainer when planning a RAAB survey. The International Centre for Eye Health maintains a list of certified RAAB trainers on its website.
More information RAAB on the ICEH website can be found here: