A landmark study has revealed the positive impact vision has on productivity by showing how a simple pair of glasses significantly improved the productivity of older Indian tea pickers.
The Prosper study (Productivity study of presbyopia elimination in rural-dwellers), sponsored by the global charity Clearly and published in Lancet Global Health, is the first ever randomised controlled trial to explore the link between clear vision and productivity. The results showed the significant effect of providing glasses to correct presbyopia in half the group of 751 mainly women tea workers aged 40 years or older, with those in the intervention group improving their productivity by 21.7%, and 31.6% for those aged over 50. The result represents the largest ever recorded productivity increase from any health intervention to date.
Study lead, Professor Nathan Congdon from Queens University in Belfast said, “We thought it was crucial to demonstrate that performance, even of tasks which may not seem obviously visual, can be boosted so impressively by glasses. Nearly 90% of workers were still wearing their glasses by the end of the study and virtually all were willing to pay to replace them if needed. People knew they were benefiting from better vision.”
The results are consistent with other research and adds to evidence showing that correction of even modest presbyopia, common at age 40 years or older, can significantly improve work productivity at low cost in a visually demanding labour setting.