Reading Glass on Livelihoods and Quality of Life in Rural Bangladesh
Condition: Presbyopia
MeSH terms: Presbyopia
Study type: Interventional

Summary: 
      The issue of uncorrected Presbyopia is an emerging health and livelihoods problem in
      Bangladesh. Presbyopia is easily corrected with an appropriate pair of reading glasses.
      Non-governmental organizations and government agencies have been working in many emerging
      markets, including Bangladesh, to increase eyeglass coverage among low-income adults by
      introducing basic vision screening and the dispensing of reading glasses at the community
      level. While vision screening is typically considered a health intervention, the primary
      motivation of these organizations and government agencies is to correct blurry vision with
      the intention of improving adults' income earning potential.

      VisionSpring and BRAC (previously known as Bangladesh Rural Advancement Committee) are two
      such NGOs who are partnering to implement a "Reading Glasses for Improved Livelihoods"
      program. VisionSpring is a social enterprise with a mission to increase access to affordable
      eye care and glasses in low-income settings. BRAC is an international development
      organization dedicated to alleviating poverty by empowering the poor.

      VisionSpring and BRAC have initiated a Randomized Control Trial to assess the economic and
      social impact that reading glasses may have on individuals that earn less than $4 a day. The
      study hypothesizes that post-intervention, the adoption of reading glasses will increase
      productivity related to paid work, and will enhance the vision-related quality of life of
      adults with Presbyopia.

      This experimental trial is designed to test the aforementioned hypotheses. In March 2017 a
      census survey was conducted in 59 villages of adults aged ≥35 and ≤65 years old in order to
      identify individuals with uncorrected presbyopia who would be eligible for enrollment in the
      study intervention. Following household visual acuity screenings, study participants were
      selected for enrollment. Randomization was conducted at the household level. Based on the
      inclusion criteria, a total of 824 random households were surveyed at the baseline. Following
      completion of the baseline survey, in August 2017 the treatment group was given reading
      glasses free-of-cost. The endline survey will be conducted in March 2018, eight months from
      the baseline. Although some income-related outcomes may take more time to manifest, it is
      anticipated that the wearing of glasses precipitates changes in a relatively short time
      frame. The control group will receive reading glasses at the conclusion of the endline
      survey.
    

Detailed description: 
      BRAC (previously known as Bangladesh Rural Advancement Committee) has conducted a study on
      the Assessment of the Impact of Reading Glasses on Livelihoods and Quality of Life in the
      Context of Rural Bangladesh in 2017 with financial and technical assistance from
      VisionSpring. The goal is to assess the impact of reading glasses on economic return and
      social angles for people in rural areas in Bangladesh.

      BRAC and VisionSpring have developed an experimental trial to test the effects of reading
      glasses. The study will utilize both pre and post-intervention data to identify the causal
      effects. A randomized control trial is considered to be the most rigorous method of
      determining whether a causal relationship exists between an intervention and outcome. This is
      a Randomized Control Trial (RCT) conducted at the household level.

      First, investigators selected 59 villages in Bangladesh where the BRAC/VisionSpring
      distribution of reading glasses has not been present. A census survey was carried out in the
      59 villages to identify those suffering from Presbyopia who were eligible for glasses.

      Second, participants were recruited through a household Presbyopia screening of individuals
      over 35 years old and less than 65 years old. Participants with chronic eye diseases that
      require regular and intensive treatment were excluded from the study.

      A structured questionnaire was used at the census survey where demographic information,
      income, and occupation were asked. Randomization was taken place after the census survey, and
      a study sample was selected based on the inclusion criteria of the study which are: (1) Over
      35 years of age, (2) Presbyopia positive, (3) Have never used reading glass, (4) Selective
      occupation (tailor, barber, self-employed artisan etc), (5) Willing to provide contact
      information and give informed consent.

      The study proposal defines two rounds of data collection to be conducted; baseline data
      collection was completed in August 2017 and follow-up data will be conducted in March 2018. A
      quantitative questionnaire was distributed at the baseline survey in order to understand the
      livelihoods and quality of life before the intervention began. Skilled interviewers were
      recruited for this study, and a three-day intensive training was held to reinforce the goals
      of the study. The training module was developed in Bangla to guide the interviewers in the
      field. Questions related to socio-demographic characteristics, economic status of the
      household (e.g. monthly income), the productivity of the respondent and quality of life were
      collected during baseline, and the same questionnaire will be used in the baseline survey.

      A multi-stage simple random sampling technique has been used in this study. The sample size
      of the study is pre-determined through a power calculation, the inclusion criteria of being a
      Presbyopic patient. As our primary outcome is income, a non-normally distributed parameter,
      it is better to compare proportions falling in various quartiles for sample size
      calculations. With a two-sided significance level of p=0·05 and power of 80%, to detect a 10%
      between-group difference in the proportion in the highest quartile of income (35% versus
      25%), corresponding to an odds ratio of 1.6, 349 participants would be needed in each group.
      Assuming a 15% rate of attrition based on previous studies in this population, a total sample
      of 822 persons (411 in each group) would be required.

      As the study is randomized at the individual level, there is a possibility to have the
      spillover effect. To minimize the spillover effect, one participant was selected from each
      household. There is a risk that members of the control group may see the benefits experienced
      by others in their community and buy a pair of reading glasses during the study. In an
      attempt to mitigate this risk, members of the control group were promised free glasses at the
      end of the study.

      Investigators will use a difference-in-difference analysis to estimate the impact of the
      reading glasses study based on monthly income (primary outcome), and near vision-related
      quality of life.

      To measure the quality of life, investigators will use a standardised instrument to look at
      respondents' perceptions of their facility with caregiving, household work, ability to (for
      those who are literate) mobile phone use, personal hygiene, and dependence.

      Differences in baseline characteristics by study group will be analysed using the t-test or
      Wilcoxon rank-sum test for continuous variables with or without normal distribution
      respectively, the Chi-squared or Fisher's exact test (with cell frequency<5) for binary
      categorical variables, and ordinal logistic regression for ordinal categorical variables.
      Normality will be checked using histograms and Q-Q plots.

      Data for the primary outcome will be presented as median and inter quartile range due to lack
      of normality, The change in self-reported monthly income will be categorized by quartiles and
      the unadjusted and adjusted intervention effects, odds ratio and 95% CI estimated using
      ordinal logistic regression. Unadjusted and adjusted mean between-group differences will be
      estimated for the secondary outcomes using linear regression. All variables with P<0.05 in
      the simple regression analysis will be included in multiple regression models. All
      statistical analyses will be performed using a commercially available software package (Stata
      15.1, StataCorp, College Station TX, USA).
    

Intervention name(s): Reading glass
Intervention type(s): Other
Intervention description(s): Participants from the experimental group have received reading glasses free of cost. Investigators hypothesize that a simple pair of eyeglasses could improve the lives of these people by enabling continued participation in the workforce, restoring productivity levels in both paid and unpaid work, and enhancing the ability to perform everyday tasks. Investigators also hypothesize that reading glasses will improve quality of life.
Allocation: Randomized
Intervention model: Parallel Assignment
Masking: Single (Investigator)
Primary purpose: Other
Keywords: Presbyopia; Quality of life; Reading glass; Productivity