Distance and near vision impairment and its impact on work productivity among garment industry workers in Hyderabad, Telangana, India

Abstract

We report the prevalence and impact of distance-vision (DVI) and near-vision impairment (NVI) among garment workers from a longitudinal study in Hyderabad, Telangana in India. Make-shift clinics were set up in five garment factories, and 1361 participants aged 18 years or older were examined. Presenting visual acuity (PVA) and best-corrected visual acuity (BCVA) for distance and near were evaluated. DVI was defined as PVA < 6/12 in the better eye, and NVI was defined as binocular near-vision < N6 at 40 cm among those without DVI and aged ≥ 40 years. The Work Productivity and Activity Impairment questionnaire visual analogue score was used to measure the effect of DVI and NVI on work productivity, with higher scores indicating greater impact. Among those examined, 25.6% were aged ≥ 40 years, and 87.0% were women. The prevalence of DVI was 6.9% (95% CI:5.6–8.4), and the prevalence of NVI was 52.4% (95% CI:47.1–57.8). The impact on work productivity was significantly higher in individuals with DVI compared to those without DVI (12.6 versus 8.8; p = 0.04). Scores were also higher for those with NVI than for those without NVI (13.3 versus 7.7; p < 0.01). DVI and NVI are common among garment industry workers, significantly affecting their productivity. Regular eye exams at the workplace can be beneficial.

Introduction

Vision impairment (VI) adversely affects the social, economic, and emotional well-being of an individual¹. Globally, 2.2 billion people are either near-vision or distance-vision impaired². Near-vision impairment (NVI) affects over a billion people worldwide and poses occupational and personal challenges^2,3. Worldwide, 3.3% of the population of working age has either moderate-severe vision impairment (MSVI) or is blind⁴. The United Nations Sustainable Development Goals (SDGs) mandate poverty alleviation (SDG 1), health for all (SDG 3), and decent work and economic growth (SDG 8).^1,5 Visual health, work productivity, and economic well-being are all interrelated and crucial to achieving the SDGs^1,5.

The garment-making industry employs a substantial number of people in India⁶. It is estimated that the textile and apparel industry, which also includes garment making, provides direct employment for more than 45 million people, including women and rural populations⁶. Hyderabad, situated in the southern Indian state of Telangana, is a hub for the garment manufacturing industry. It is well-organised and highly mechanised, employing several thousand people. There are many factories where readymade garments are stitched for local and international markets. The garment making process includes several near-vision-intensive tasks, such as stitching and tailoring, and working with fine thread. These tasks require precise and sustained near-vision work for prolonged periods⁷. Even the slightest vision impairment or discomfort can adversely impact productivity⁸. Understanding the prevalence of Distance Vision Impairment (DVI) and Near Vision Impairment (NVI) in this industry can help develop strategic service delivery programmes for these workers. Though a few studies have been conducted among garment factory workers in Bangladesh and craftswomen in Zanzibar, there are no such studies from Hyderabad in Telangana, which is a hub for the garment industry^7,9. The results from other occupational groups may not be applicable to this group because visual demands and work patterns differ, highlighting the need to conduct studies in this group.

The longitudinal Vision in Occupational Groups Study (VOGS) was conducted in the southern Indian state of Telangana to assess the eye health status among three occupations engaged in close, near work. It included workers from garment factories in Hyderabad, cloth weavers in Pochampally, Yadadri Bhuvanagiri district, and goldsmiths and jewellery makers in Hyderabad. This first paper from VEOGS reports on the prevalence of DVI and NVI and their impact on daily activities and work productivity among garment factory workers in Hyderabad.

Methods

Ethics approval

The Institutional Review Board (IRB) of the Hyderabad Eye Research Foundation, L V Prasad Eye Institute (LVPEI), India, approved the study protocol (Protocol No: LEC 09-19-325). The study adhered to the principles outlined in the Declaration of Helsinki. Written informed consent was obtained from each participant after explaining the procedures and before starting the eye examination. A copy of the consent form was provided to each participant for their records.

Sample size and selection

The sample size for the study was calculated with an anticipated prevalence of 6% for distance vision impairment (DVI), a 95% confidence interval, a precision of 20%, and a non-response rate of 10%. The minimum sample size required was 1450 participants. This sample is also sufficient to detect a 10% difference in work productivity among those with and without vision impairment. We selected five factories in the western and northeastern industrial zones in Hyderabad, within a 50 km radius of the base referral centre, LVPEI. Workers aged 18 years and older who had worked in those factories for at least 3 months and were willing to participate were included in the study. The data collection was conducted between 2021 and 2023, with a few breaks due to the pandemic. COVID-19 protocols were followed during data collection, which took place during the pandemic.

The study coordinator mapped the locations and visited the factories in person. The human resources department was contacted, and permission was obtained to step up the clinics for the study. The human resources department facilitated eye examinations while minimising disruption to their work ensuring close to 100% participation.

Clinical examination

‘Make-shift clinics’ were set up at each study location. These clinics are designed to replicate the standard clinical eye examination rooms found in an eye clinic, featuring typical lighting conditions and workstations. Illumination was measured using a light meter. Two workstations were set up. All eye examinations were conducted by trained optometrists and assisted by vision technicians. Three optometrists were involved in clinical examinations. Detailed ocular history including spectacle use and ocular symptoms were recorded. Distance visual acuity (VA) was measured using the standard logarithm of the minimum angle of resolution (logMAR) chart under good illumination (at least 180 lux measured by a light meter). The VA was tested with the participant’s current refractive correction, if any. Additionally, pinhole visual acuity was recorded. Near vision was measured at 40 cm using the logMAR near-vision “E” chart, with any current refractive correction in place. The letter-by-letter scoring method was used to measure both distance and near visual acuity with the logMAR chart.

The external examination included examining the eyelids and ocular adnexa. Ocular motility was assessed on all participants. Refraction was performed for all participants with a distance vision worse than 6/6 or near vision worse than N6 in either eye. The presenting VA was assessed (aided vision in cases of those who were using glasses and unaided among those without glasses). Best-corrected distance VA and near vision were assessed after refraction. A detailed binocular vision and dry eye assessment was also conducted. Eye examinations were conducted using a slit lamp (Haag Streit BA 904, USA) with the participant and the examiner seated in a comfortable position. The fundus examination and retinal photography were performed using a non-mydriatic fundus camera (Visuscout 100 Handheld Fundus Camera, Carl Zeiss Meditec, Inc., USA). Two images were captured for each eye, one optic disc-centred image and another macula-centred image. These images were graded by trained graders. The questionnaires included personal, socio-demographics, systemic history, and other information. The questionnaires were administered by two trained field investigators before the eye examination. All participants were provided with spectacles at ‘no cost’ where indicated. Working distance was considered when dispensing the spectacles. All those who needed any further treatment were referred to LVPEI for management. All services are provided at ‘no cost’ to the participants.

Assessment of work productivity and activity limitation

The Work Productivity and Activity Impairment (WPAI) questionnaire was used by two field investigators to assess the impact of DVI and NVI on routine daily activities and work productivity¹⁰. The WPAI is a validated questionnaire used in studies investigating different health conditions and study designs, including clinical trials, to compare changes in work productivity between intervention and control groups^11–18. The standard WPAI questionnaire was modified to include eye health and vision instead of general health. As part of this, two questions were asked about how much the eye problems affected their productivity and their regular daily activities outside of work. The responses to both questions were rated on a 10-point visual analogue scale (VAS), ranging from 0 (no effect) to 10 (maximum effect). These scores were rescaled from 0 to 100 for analysis. This questionnaire was administered in the local language.

Definitions

We used the World Health Organisation categories of VI proposed by the Vision Loss Expert Group¹⁹. As per this definition, DVI is divided into four categories based on presenting VA in the better eye, namely Mild VI (VA worse than 6/12 to 6/18), Moderate VI (VA worse than 6/18 to 6/60), Severe VI (worse than 6/60 to 3/60), and Blindness (worse than 3/60 to no perception of light). Similarly, NVI was defined as binocular near-vision worse than N6 (logMAR 0.3) in the better eye at 40 cm and no VI for distance among those aged 40 years or older. NVI was further categorised into mild NVI (N8-N10), moderate NVI (N12-N32), and profound NVI (worse than N32). Based on the type of tasks performed by the participants, the nature of near work was divided into mild (cutting, laying, and marking), moderate (ironing, packing, and stickering) and intensive (stitching, quality checking, trimming, and collar designing) near work tasks.

Data management and analysis

Data were collected from each participant using custom-designed data forms compiled into a folder. After data collection, the folders were sent to the data centre, and the data were entered into a Microsoft Access database. Data were analysed using Stata Statistical Software, Version 14 (StataCorp, College Station, Texas, USA). Descriptive statistics were used to report the mean and proportions. Prevalence estimates were calculated and presented with 95% confidence intervals. Multivariable analysis (multiple logistic refression) was performed to investigate the relationship between DVI and other socio-demographic variables, including age, gender, and type of tasks. Adjusted odds ratios (OR) with 95% confidence intervals are presented. Statistical significance was set at p ≤ 0.05.

Data availability

The datasets used and/or analysed during the current study are available from the corresponding author on reasonable request.

Results

Among the 1361 participants examined, the mean age was 34.6 years (SD: 8.1 years; range: 18–62 years) and 87.0% (n = 1184) were women. Most participants were involved in intensive near-vision tasks (79.6%; n = 1083), followed by moderate (9.1%; n = 124) and mild-intensive tasks (11.3%; n = 154).

Distance vision impairment (DVI)

The overall prevalence of DVI was 6.9% (95% CI: 5.6–8.4; n = 94). The DVI was significantly higher among older age groups and for those performing mild intensity tasks. (Table 1) Based on VI categories, 4.0% (95% CI: 3.1–5.2; n = 55) of participants presented with mild VI and 2.9% (95% CI: 2.0-3.9; n = 39) of participants presented with moderate VI. DVI declined from 6.9% (n = 94) to 1.0% (n = 13) after refraction. (Fig. 1) The most common cause of DVI was uncorrected refractive errors (90.4%; n = 85), followed by cataracts (4.2%; n = 4) and other diseases (5.4%; n = 5). (Table 1)

Table 1.

Prevalence of distance vision impairment in the garment factory workers.

Distance VI	n	Normal (row %)	VI (row %)	p-value (chi-squared test)
Age (years)
18–29	373	358 (96.0)	15 (4.0)	< 0.01
30–39	588	560 (95.2)	28 (4.8)
40–49	350	314 (89.7)	36 (10.3)
≥ 50	50	35 (70.0)	15 (30.0)
Gender
Male	177	163 (92.1)	14 (7.9)	0.573
Female	1184	1104 (93.2)	80 (6.8)
Tasks
Mild intensity tasks	154	128 (83.1)	26 (16.9)	< 0.01
Moderate intensity tasks	124	117 (94.4)	7 (5.6)
High intensity tasks	1083	1022 (94.4)	61 (5.6)
	1361	1267 (93.1)	94 (6.9)

Fig. 1.

Distance and near vision impairment based on presenting and best corrected visual acuity.

In multiple logistic regression analysis, the odds of DVI increased with age, being highest among those aged 50 years and older (OR: 8.8; 95% CI: 3.9–20.1). Although the odds of DVI were higher for women (OR: 1.2; 95% CI: 0.6–2.3), it was not statistically significant. The odds of VI were higher among those involved in mildly intense tasks (OR: 2.8; 95% CI: 1.7–4.7). (Table 2)

Table 2.

Multiple logistic regression analysis showing the association between Distance visual impairment and socio-demographic variables.

	Odds ratio	95% CI	p-value
Age (years)
18–29	Reference
30–39	1.2	0.6–2.3	0.583
40–49	2.6	1.4–4.8	0.003
≥ 50	8.8	3.9–20.1	< 0.01
Gender
Male	Reference
Female	1.2	0.6–2.3	0.601
Task
High intensity tasks	Reference
Moderate intensity tasks	1.1	0.5–2.4	0.880
Mild intensity tasks	2.8	1.7–4.7	< 0.01

Near vision impairment (NVI)

In total, 400/1361 (29.3%) participants were aged ≥ 40 years. After excluding the 51 participants with DVI, the remaining 349 participants were included in the NVI analysis. The prevalence of NVI was 52.4% (95% CI: 47.1–57.8; n = 183). (Table 3). Based on presenting near-vision, 43.8% (95% CI: 38.6–49.2; n = 153) had mild NVI, and 8.6% (95% CI: 5.9–12.0; n = 30) had moderate NVI. The NVI declined from 52.4% (n = 183) to 6.6% (n = 23) with refractive correction and near addition. (Fig. 1)

Table 3.

Prevalence of near vision impairment.

Near VI	n	Normal (%)	NVI (%)	p-value
Age (years)
40–49	314	143 (45.5)	171 (54.5)	0.023
≥ 50	35	23 (65.7)	12 (34.3)
Gender
Male	50	23 (46.0)	27 (54.0)	0.811
Female	299	143 (47.8)	156 (52.2)
Task
Mild intensity tasks	47	20 (42.6)	27 (57.4)	0.111
Moderate intensity tasks	29	9 (31.0)	20 (69.0)
High Intensity tasks	273	137 (50.2)	136 (49.8)
	349	166 (47.6)	183 (52.4)

Impact of DVI and NVI on daily routine activity and work productivity

For routine daily activities, the mean WPAI VAS score was higher among those with DVI than among those without VI though it was not statistically significant (5.1 versus 3.7; p = 0.27). However, for work productivity, the WPAI VAS scores were significantly higher among those with DVI than among those without DVI (12.6 versus 8.8; p = 0.04). Similarly, for routine daily activities, mean WPAI VAS scores were comparable among those with and without NVI (p = 0.1). However, the WPAI VAS score was significantly higher for those with NVI than for those without NVI (13.3 versus 7.7; p < 0.01). The VAS scores were higher for both with DVI and NVI, indicating their adverse impact on work productivity.  (Table 4)

Table 4.

Impact of distance and near vision on routine activities and work productivity scores.

	Vision impairment
	Present	Absent
	Mean (Standard Error)	Mean (Standard Error)	Mean difference (Standard Error)	Relative difference (%)	p value
Distance vision ( n  = 1361)
Routine activities	5.1 (1.3)	3.7 (0.3)	1.4 (1.3)	37.8	0.27
Work productivity	12.6 (2.0)	8.8 (0.5)	3.9 (1.9)	44.3	0.04
Near vision ( n  = 349)
Routine activities	4.2 (0.9)	4.1 (1.0)	0.1 (1.4)	2.4	0.1
Work productivity	13.3 (1.5)	7.7 (1.3)	5.6 (2.0)	42.1	< 0.01

Discussion

Seven out of every hundred workers in garment-making factories have DVI. Additionally, over half of those aged 40 and above have NVI. Uncorrected refractive errors are the main cause of DVI, while uncorrected presbyopia primarily causes NVI. Both conditions can be addressed with spectacles. Very few studies have reported the prevalence of VI based on occupational groups in India. In Andhra Pradesh, the prevalence of DVI was 30% among the fishing community and 14% among the cloth-weaving community, respectively^20,21. A study conducted among spinning and winding workers in a textile factory in Madurai, Tamil Nadu, India, reported that 8.8% of the workers had DVI²². This variation in DVI prevalence across Andhra Pradesh, Madurai, and the current study could be attributed to factors such as age groups, case definitions, locations, and work profiles. DVI has also been reported in occupational groups in other regions of the world. The prevalence of DVI among craftswomen in Zanzibar, Tanzania, was 29.7%.⁹ The prevalence of mild VI and moderate VI among garment workers in Bangladesh was 5.37% and 2.91% in the rural and urban areas, respectively⁷. A similar trend was observed for the prevalence of mild and moderate vision impairment in this study. The lower prevalence in workplaces compared to population-based studies could also be due to the healthy worker effect, where workers with very poor vision are either unemployed or removed from the workforce because of job demands and requirements⁹.

The prevalence of DVI was higher among older age groups (30.0%) in the weaving communities of Prakasam district, Andhra Pradesh, India²⁰. In Bangladesh, the prevalence was 14.9% among garment workers aged ≥ 40 years⁷ and the study in Zanzibar reported that those ≥ 55 years had five times higher odds of VI.⁹ Our study also showed similar findings. A few studies also reported the prevalence of NVI in occupational groups in India. In this study, the prevalence of NVI was 52.4%. A similar study conducted in Bangladesh in 2022 involving female garment workers aged 18–70 reported the prevalence of NVI as 26.8%.⁷ Marmamula S et al. conducted studies among marine fishing (2012) and weaving communities (2013) in Prakasam district, Andhra Pradesh^20,23. Although both groups had similar age distributions, the prevalence of NVI was 40.1% among the fishermen and 35% among the weavers, which is lower than the findings of this study (52.4%).^20,21

While DVI and NVI do have a significant impact on routine daily activities, the effect on work productivity is remarkable, as assessed by the work productivity and impairment questionnaire. A relative difference of more than 40% was found in scores for both DVI and NVI, suggesting a significant impact on the work productivity of the workers in these factories. Similar findings were reported from other regions on these various occupational groups^4,8,24. 

Results from the PROSPER study show an increase in the mean productivity of picking tea leaves by 5.25 kg per day and a substantial increase in income was noted after an intervention with spectacles⁸. Several other studies have reported a relationship between eye health interventions, such as dispensing spectacles and cataract surgeries, and work productivity, and their impact on the United Nations (UN) Sustainable Development Goals^4,8,24. Therefore, improving eye health can improve productivity, reduce poverty (SDG 1), and help attain the SDGs set by the UN.^1,5

Globally, 30.2% of the population with MSVI had a relative reduction in employment⁴. This may affect their productivity and hinder their ability to retain employment in the workforce. After spectacles were provided, there was a 10–20% increment in work productivity among spinners and a 10% increment among winding workers, showing the positive impact of spectacle correction²². More women were employed in the garment industry compared to other occupations⁷. Women tend to have lower employment opportunities, lower levels of education, and limited access to health care because of gender-specific barriers⁷. Providing eye care to women at workplaces is likely to address access related barriers, help generate more income, and contribute to the economic well-being of the family⁹. Vision plays a crucial role in garment making, as it involves numerous intricate, visually intensive tasks. Good vision enables garment workers to achieve precision in stitching, intricate detailing, and accurate measurements, resulting in high-quality output. This study highlights the importance and necessity of regular eye check-ups and the dispensing of spectacles for both distance and near vision among garment makers.

This is the first study to map the prevalence of DVI and NVI among garment makers in Hyderabad, Telangana, India. Additionally, this study reported on the impact of DVI and NVI on performance in daily routine activities and work productivity. The results of this study can be extrapolated to the people working in garment-making factories with similar work profile in other parts of India. Timely interventions can help improve the productivity and enhance quality of the products by garment workers by minimising the errors, delays, and injuries related to work tools.

Lack of time, inconvenient timings, and fear of losing pay (due to absenteeism) may be key barriers to the uptake of services. Providing services closer to the workplace and at regular intervals is likely to result in productivity gains and contribute to the achievement of the SDGs. On-site service provision will reduce loss to follow-up and logistics costs associated with multiple visits to eye care centres.

In this study, women outnumbered men, which reflects the employment pattern in these factories. One limitation of the study is its reliance on the WPAI questionnaire, which provides a subjective measure of work productivity. The work productivity was not measured objectively in this study. Although attempts were made to collect financial information, most of the workers and management were reluctant to provide it. Grundy’s nomogram is an important tool in occupational eye health and visual task assessments²⁵. However, this tool was not used in all the cases in the current study. Future studies can consider including this tool for visual task analysis. Furthermore, the results from our study cannot be extrapolated to other occupational groups, as different occupations have varying visual requirements and work profiles.

In conclusion, our study reported a significant burden of correctable DVI and NVI among garment industry workers, impacting their work productivity. This study also provided a basis for understanding the vision needs of garment workers and for providing appropriate, timely interventions to improve their well-being.

Author contributions

SM conceived the idea, designed and conducted the study and analysed the data. VM was involved in data collection and quality control and also drafted the first version of the manuscript. DN and TRK were involved in data collection and manuscript revision. All the authors have approved the final version of the manuscript. SM is responsible for the overall content as a guarantor.

Funding

This study was funded by the Hyderabad Eye Research Foundation (HERF) (India), Lions Clubs International Foundation (USA), SightFirst Research grant (SFP2107/UND).

Data availability

The datasets generated during the study are not publicly available as further data analysis is being carried out. The data can be made available from the corresponding author on a reasonable request.

Declarations

Competing interests

The authors declare no competing interests.