Free near glasses improve productivity and ROI in Indian garment factories

The PROSPER II study (NCT04629820),¹ published in the British Journal of Ophthalmology, is a randomized controlled trial conducted in garment factories that describes the global economic impact of providing very inexpensive glasses to correct near vision to this population of factory workers in India, according to a press release.

The study was conducted by researchers from VisionSpring and Queen’s University Belfast, with support from USAID.

The key study findings enumerated in a press release are as follows:

• “Scaling vision correction across the global textile and garment sector would generate an additional $27 billion a year.
• The intervention gave a 337% net return on investment over the 3-month trial period.
• Glasses provision could boost the economies of lower-income countries where the majority of garments are produced and the industry is under significant strain.
• Eyeglasses to correct near vision boosted factory worker productivity by almost 6%.
• One in 4 (27%) sewing machine operators have uncorrected visual impairment.
• India’s largest apparel manufacturer, Shahi Exports, is committed to a vision correction program for 100,000 workers across all of its factories.”

This is the first time such study conducted on a factory production line and the findings are significant because of pressure on the garment industry as a result of tariffs, energy prices, and intense competition, which has led to large numbers of factory closures, according to the press release.

Ella Gudwin, Chief Executive of VisionSpring and co-author of the study, said,“Eyeglasses are one of the simplest and most cost-effective ways to improve productivity in a factory. For factory owners in a highly competitive sector, having a workforce that can see clearly is an essential competitive advantage. Ministries of Labor in countries with large manufacturing workforces, including apparel and footwear, could achieve a rapid injection of economic growth by ensuring all workers see well to do well.”

Nathan Congdon, Chief Investigator for the PROSPER II study, Ulverscroft Chair of Global Eye Health at Queen’s University Belfast and Director of Research for Orbis International, commented, “There has been interest for many years in vision program for the garment manufacturing industry, and for obvious reasons: this sector contributes enormously to the economies of many countries and offers unique employment opportunities, especially for rural communities and for women. But the lack of reliable trial-based evidence that glasses could significantly improve worker productivity has held the field back. PROSPER II now provides that evidence, showing that a simple pair of glasses can improve productivity at a level comparable to far more complex interventions such as management training, at a fraction of the cost per worker.”

PROSPER II study

Shahi Exports provided free glasses to sewing machine operators, who were experiencing presbyopia.

The study included vision screening, glasses to correct near vision, and encouragement to wear the glasses that cost about $10 USD for each worker.

Among 4,990 potentially eligible workers, 3,648 (73.1%) underwent eye examinations, and 682 (18.7%) (mean age 41.0 years, 99.0% female) were enrolled and randomized to receive either glasses (344) or to the control group (338).

All participants completed the 12-week observation. The participants who received glasses (difference=0.0325, 95% confidence interval [CI] 0.006 to 0.060, P=0.017) showed significantly greater productivity by 5.70% (95% CI 1.04% to 10.4%), the investigators reported.

Shahi Exports announced plans to provide free vision screening across its factory workforce of around 100,000 workers.

The investigators concluded, “Free near glasses confer a significant productivity benefit in this factory setting, and are substantially less costly than other successful interventions, such as management training.”

Reference:

1. Pant S, Bagwe S, Esther S, et al. PROductivity Study of Presbyopia Elimination in gaRment workers (PROSPER II): a randomised trial on the productivity impact of providing near glasses to Indian garment factory workers. Br J Ophthalmol. Epub ahead of print: April 28, 2026. doi:10.1136/bjo-2025-328563