The Impact of Providing Eyeglasses on Academic Outcomes of Disadvantaged Students: Evidence from a Randomized Trial in Florida Elementary Schools

Last registered on November 08, 2023

Pre-Trial

Trial Information

General Information

Title
The Impact of Providing Eyeglasses on Academic Outcomes of Disadvantaged Students: Evidence from a Randomized Trial in Florida Elementary Schools
RCT ID
AEARCTR-0000167
Initial registration date
December 10, 2013

Initial registration date is when the trial was registered.

It corresponds to when the registration was submitted to the Registry to be reviewed for publication.

First published
December 10, 2013, 5:38 PM EST

First published corresponds to when the trial was first made public on the Registry after being reviewed.

Last updated
November 08, 2023, 10:58 PM EST

Last updated is the most recent time when changes to the trial's registration were published.

Locations

Primary Investigator

Affiliation
University of Minnesota

Other Primary Investigator(s)

PI Affiliation
St. Catherine University

Additional Trial Information

Status
Completed
Start date
2011-08-01
End date
2014-06-30
Secondary IDs
Prior work
This trial does not extend or rely on any prior RCTs.
Abstract
This study evaluates a field experiment in which a non-profit organization (FLVQ) offered enhanced vision services to a randomly selected group of Title 1 elementary schools in three large central Florida school districts during the fall of the 2011-2012 school-year. This is the first study in the U.S. to use a randomized trial to estimate the impact of vision services on student outcomes. In order to rigorously test of the efficacy of FLVQ’s services, we conducted a randomized trial targeting 4th and 5th grade students in Title 1 schools where FLVQ had not had a significant presence over the last two years. The randomization was done at the school level in three school districts (i.e. three counties). Schools were assigned to one of two intervention groups or to a control group. The first intervention group received additional/enhanced vision screening. The second intervention group received additional/enhanced vision screening as well as free onsite eye exams by an optometrist and free eyeglasses as needed. The control group received no vision services from FLVQ. Preliminary results find that providing additional/enhanced screening alone is not enough to improve student outcomes. In two of the three school districts studied, the intervention which included free exams by an optometrist and free eyeglasses as needed significantly improved student achievement as measured by the FCAT. When we focus on these two school districts, we find that, averaging over all students – including those who did not receive eyeglasses – FCAT level scores (which range from 1-5) increased on the order of 0.08 for reading and 0.09 for math in schools where FLVQ provided screenings and follow-up vision services. This evidence is robust to different specifications and the effect is stronger for low-income students and for students with poor vision. This is a large effect and suggests that vision services are more cost-effective than many other potential uses of district and/or state funds. These preliminary results are based on data from the 2012 FCAT. When the test was administered, students who received free eyeglasses had had their glasses for only a few months. Future drafts will include data for the 2013 FCAT to track the effect over time.
External Link(s)

Registration Citation

Citation
Glewwe, Paul and Kristine West. 2023. "The Impact of Providing Eyeglasses on Academic Outcomes of Disadvantaged Students: Evidence from a Randomized Trial in Florida Elementary Schools." AEA RCT Registry. November 08. https://doi.org/10.1257/rct.167-4.0
Former Citation
Glewwe, Paul and Kristine West. 2023. "The Impact of Providing Eyeglasses on Academic Outcomes of Disadvantaged Students: Evidence from a Randomized Trial in Florida Elementary Schools." AEA RCT Registry. November 08. https://www.socialscienceregistry.org/trials/167/history/200535
Sponsors & Partners

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Experimental Details

Interventions

Intervention(s)
The first intervention group received additional/enhanced vision screening. The second intervention group received additional/enhanced vision screening as well as free onsite eye exams by an optometrist and free eyeglasses as needed. The control group received no vision services from FLVQ.
Intervention Start Date
2011-08-01
Intervention End Date
2012-03-01

Primary Outcomes

Primary Outcomes (end points)
Scores on the Florida Comprehensive Achievement Test
Primary Outcomes (explanation)

Secondary Outcomes

Secondary Outcomes (end points)
Secondary Outcomes (explanation)

Experimental Design

Experimental Design
The randomization was done at the school level in each of three school districts (i.e. three counties), for students in grades 4 and 5. Schools were assigned to one of two intervention groups or to a control group. Only Title 1 schools were included. Schools were ranked by prior test scores, and randomization was done in blocks defined by prior test scores.
Experimental Design Details
Randomization Method
Done using random number generator in an Excel spreadsheet.
Randomization Unit
Schools
Was the treatment clustered?
Yes

Experiment Characteristics

Sample size: planned number of clusters
88 schools.
Sample size: planned number of observations
18,000 students
Sample size (or number of clusters) by treatment arms
Control schools: 43
Screen only schools: 23
Full treatment schools: 22
Minimum detectable effect size for main outcomes (accounting for sample design and clustering)
IRB

Institutional Review Boards (IRBs)

IRB Name
University of Minnesota Institutional Review Board
IRB Approval Date
2011-10-13
IRB Approval Number
1109S04064

Post-Trial

Post Trial Information

Study Withdrawal

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Intervention

Is the intervention completed?
Yes
Intervention Completion Date
January 31, 2012, 12:00 +00:00
Data Collection Complete
Yes
Data Collection Completion Date
May 16, 2013, 12:00 +00:00
Final Sample Size: Number of Clusters (Unit of Randomization)
76 schools
Was attrition correlated with treatment status?
No
Final Sample Size: Total Number of Observations
15,422 pupils
Final Sample Size (or Number of Clusters) by Treatment Arms
38 control schools 19 schools provided vision screening, but no offer of free eyeglasses 19 schools provided both vision screening and free eyeglasses offered to students with vision problems
Data Publication

Data Publication

Is public data available?
No

Program Files

Program Files
No
Reports, Papers & Other Materials

Relevant Paper(s)

Abstract
More than 20 percent of all school-aged children in the United States have vision problems, and low-income and minority children are disproportionately likely to have unmet vision care needs. Vision screening is common in U.S. schools, but it remains an open question whether screening alone is sufficient to improve student outcomes. We implemented a multi-armed randomized controlled trial (RCT) to evaluate the impact of vision screening, and of vision screening accompanied by eye exams and eyeglasses, provided by a non-profit organization to Title I elementary schools in three large central Florida school districts. We find that providing additional/enhanced screening alone is generally insufficient to improve student achievement in math and reading. In contrast, providing screening along with free eye exams and free eyeglasses to students with vision problems improved student achievement as measured by standardized test scores. We find, averaging over all students (including those without vision problems), that this more comprehensive intervention increased the probability of passing the Florida Comprehensive Achievement Tests (FCATs) in reading and math by approximately 2.0 percentage points. We also present evidence that indicates that this impact fades out over time, indicating that follow-up actions after the intervention may be necessary to sustain these estimated achievement gains.
Citation
Glewwe, Paul, Kristine West and Jongwook Lee. 2018. "The Impact of Providing Vision Screening and Free Eyeglasses on Academic Outcomes: Evidence from a Randomized Trial in Title I Elementary Schools in Florida". Journal of Policy Analysis and Management 37(2):265-300.

Reports & Other Materials