Clinical trial NCT04654013: PROductivity Study of Presbyopia Elimination in Rural-dwellers III
Official title: Effects of Near Vision Spectacle Correction on Work Retention Among Textile Factories Workers in India
Study type: INTERVENTIONAL
Overall status: ACTIVE_NOT_RECRUITING
Phase: NA
Conditions: Presbyopia
Keywords: Presbyopia
Refractive error
Work retention
Spectacle wear compliance
Work efficiency
Lead sponsor: Queen's University, Belfast
Sponsor class: OTHER
Collaborators: name: VisionSpring
name: Clearly
name: University of Michigan
name: Good Business Lab
name: Zhongshan Ophthalmic Center, Sun Yat-sen University
First posted: 2020-12-04
Enrollment: 1291
Sex: ALL
Minimum age (years): 30
Standard ages: ADULT
OLDER_ADULT
Accepts healthy volunteers: no
Allocation: RANDOMIZED
Intervention model: PARALLEL
Intervention model description: 1260 workers aged 30 years and above with uncorrected presbyopia will be randomized to receive free glasses within one week of undergoing vision assessment, or free glasses at the end of the study assessment (18 months after vision assessment).
Primary purpose: TREATMENT

Brief summary: The investigators will conduct an embedded mixed methods study in which the primary approach is a randomized controlled trial (RCT), and the secondary or embedded approach is a descriptive qualitative study. The aim of the RCT is to assess the impact of presbyopic correction on workplace productivity and retention in the textile industry in a low middle-income country. Additional qualitative data will be collected to enhance understanding of factors linked to reasons why enrolled sew-ers left their job during the study. Participants will be textile workers aged 30 years and above with uncorrected presbyopia who are employed by Shahi Exports Private Limited in Karnataka, India.

Detailed description: Globally, 1.1 billion people lack a simple pair of reading glasses to correct impaired near vision, called presbyopia. Presbyopia can begin as early as age 30 years, commonly becomes functionally apparent by 40, and is essentially complete by 55 meaning that presbyopia is most common at the height of the working years. The global productivity loss due to uncorrected presbyopia has been estimated to exceed US$25 billion, and presbyopia is shown to be associated with significant impairment in activities of daily living. There is paucity in trial evidence of the impact on near vision spectacle correction on work productivity and workplace retention. The largest reported effect sizes among such trials (specifically for productivity) was the PROSPER trial, which showed that providing inexpensive near vision glasses increased the daily weight of tea picked among presbyopic, mostly-female Indian agricultural workers by more than 5 kg (21.7%) compared to those in the control group.

Study Plan: The investigators will choose 1260 textile workers aged 30 years and above with uncorrected presbyopia who are employed by Shahi Exports Private Limited in Karnataka, India. They will be randomly assigned into one of two groups: a group receiving free reading glasses within one week of undergoing vision assessment ("Intervention") or a group receiving identical reading glasses at the end of the assessment period ("Control").The main study outcome will be the proportion of workers who continue working at the factories in the intervention group (as opposed to control). The investigators anticipate that the glasses intervention will increase retention by 20% in the Intervention group at 1 year.

The study will also assess the workers' efficiency, why they have left employment, how satisfied and valued they felt at their work and how often they use their glasses for work. These other outcomes will help the investigators to better understand the causal pathway between vision and work retention. The investigators will also study the total cost of providing glasses per additional worker retain their employment.

Research question: Will providing free glasses to presbyopic Indian textile workers increase work retention?

Design: Investigator-masked, multi-center randomized controlled trial with a qualitative component

Rationale: Although presbyopia is safely, effectively and inexpensively treated with glasses, rates of optical correction in LMICs are as low as 10%. The way in which firms manage workers has profound implications for performance by way of worker attendance, retention, and productivity. Similarly, worker engagement, and the extent to which workers feel valued, is a key determinant of firm performance. As the low-skill workforce in many developing countries transitions rapidly from agriculture to industrial work, employers struggle with high worker turnover due to poor working conditions, low pay, and restricted worker rights. Few trials have been published which address the question of whether healthcare interventions can improve work performance as well as workplace retention, especially among persons over the age of 40 in low and middle-income countries (LMICs). There is interest in understanding if these results obtained in an agricultural setting can be extended to other financially-important sectors.

Methods: The investigators will choose 1260 textile workers aged 30 years and above with uncorrected presbyopia who are employed by Shahi Exports Private Limited in Karnataka, India. They will be randomly assigned into one of two groups: a group receiving free reading glasses within one week of undergoing vision assessment ("Intervention") or a group receiving identical reading glasses at the end of the assessment period ("Control").

The main outcome 18 month later will be work retention; secondary outcomes are workers' efficiency, the reasons the workers left their employment, satisfaction and perceived self-valued at work and glasses wear adherence at work. Attitudes about presbyopia and spectacle use and intervention cost-effectiveness will be studied.

Eligibility criteria: Inclusion Criteria:

* Aged 30 years and above
* Distance visual acuity \>= 6/12 in both eyes
* Presence of presbyopia, defined as the inability, correctable with reading glasses, to read the N8 line using both eyes together, on a tumbling near vision chart at a distance of 25cm, 30cm, 40cm, and 50cm based on workers working distance
* Employed at the factory for \>=3months in the sewing department

Exclusion Criteria:

* Current ownership of reading or distance glasses (regardless of accuracy)
* Obvious evidence of ocular disease in either eye detected during the eye examination, or history of such disease based on self-report
* Low likelihood of completing follow-up in the study due to current plans to move out of the area or leave employment at Shahi during the follow-up period

Primary outcomes:
measure: Work retention
timeFrame: September 2022 to May 2024; Over the 18 month follow-up period from enrolment to study completion
Secondary outcomes:
measure: Compliance with spectacle wear
timeFrame: 3, 6, 9, 12, 15 and 18 months after enrolment
measure: Change in work satisfaction
timeFrame: Between baseline and 3, 6, 9, 12, 15 and 18 months after enrolment
measure: Change in feeling valued-at-work
timeFrame: Between baseline and 3, 6, 9, 12, 15 and 18 months after enrolment
measure: Change in likeliness to stay at work
timeFrame: Between baseline and 3, 6, 9, 12, 15 and 18 months after enrolment
measure: Change in work efficiency
timeFrame: Between baseline and 3, 6, 9, 12, 15 and 18 months after enrolment
measure: Attitudes towards vision correction
timeFrame: At month 0
measure: Access to local eyecare services
timeFrame: At month 0
measure: History of uptake of eyecare services
timeFrame: At month 0
measure: Change in Quality of Life as assessed by the THRIVE Near Vision Quality of Life tool
timeFrame: Between baseline and endline at 18 months
measure: Reasons leaving employment at Shahi
timeFrame: 2 months within participants leaving employment
measure: Change in work productivity
timeFrame: Between baseline and 3, 6, 9, 12, 15 and 18 months after enrolment
measure: Cost effectiveness of intervention
timeFrame: At study closeout at 18 months
measure: Change in skill grade
timeFrame: Between baseline and endline at 18 months
measure: Change in monthly wage
timeFrame: Between baseline and endline at 18 months
Other outcomes:
Locations:
city: Bengaluru
country: India
facility: Good Business Lab
state: Karantaka
Study officials:
affiliation: Queen's University, Belfast
name: Nathan G Congdon, MD, MPH
role: PRINCIPAL_INVESTIGATOR
References: