Education · Research

Clinical Studies & Research

Parents and referring professionals ask us the same fair question: where is the evidence? These are the clinical trials, reviews and research summaries we point people to on optometric vision therapy — with a short, plain-English note on what each one actually looked at.

6 studies & summaries NEI-funded clinical trial Read them yourself

Jump to the Studies Does Vision Therapy Work?

Before You Read

How to Use This Page

Vision therapy is a clinical treatment, and like any treatment it should be judged on what it has been shown to do for a specific diagnosis — not on a blanket opinion in either direction. The papers below are the ones we hand to parents who want to read the research themselves, and to the optometrists, pediatricians, teachers and therapists who send us patients. They cover two threads: the effect of vision therapy on convergence insufficiency and other non-strabismic focusing and eye-teaming disorders, and the wider body of work on how vision relates to reading and learning.

Read them with the usual caution. A summary is not a full paper, several of these documents are collections rather than single trials, and none of them can tell you what is happening with your own child or your own eyes. Research narrows the question; a developmental vision evaluation answers it. This page is educational and is not medical advice.

Where a document is still available from its publisher — or, for the first paper, from the free PubMed Central archive — we have linked straight to it, so you can read the original rather than our description of it. Links open in a new tab.

The Evidence

Clinical Trials & Peer-Reviewed Research

Individual studies and reviews on the outcomes and the scientific basis of optometric vision therapy.

Improvement in Academic Behaviors After Successful Treatment of Convergence Insufficiency

Borsting E, Mitchell GL, Kulp MT, Scheiman M, Amster DM, Cotter S, et al.; Convergence Insufficiency Treatment Trial Study Group (2012). “Improvement in Academic Behaviors After Successful Treatment of Convergence Insufficiency.” Optometry and Vision Science 89(1):12–18. doi:10.1097/OPX.0b013e318238ffc3

A six-item survey was designed to quantify how often adverse school behaviors occurred, and how concerned parents were about school performance. It was given to 218 children, aged 9 to 17, before they started vision therapy and again after 12 weeks of treatment.
Scores were significantly better for the children who were successful or improved after vision therapy than for the children who did not respond to it.

The takeaway: Successful optometric vision therapy is associated with a reduction in the frequency of adverse academic behavior — and in parental concern about reading and schoolwork — as reported by parents.
Read the full paper (PubMed Central)
The journal link carried on our previous site was a publisher “page not found” address and no longer resolves, so we link the paper’s permanent record instead.
A Randomized Clinical Trial of Treatments for Convergence Insufficiency in Children

The National Eye Institute — a division of the National Institutes of Health, part of the U.S. Department of Health and Human Services — funded this study to determine the most effective treatment for convergence insufficiency. It was a double-blind, masked study, with optometrists and ophthalmologists collaborating.
It ran at nine sites throughout the United States, including the Mayo Clinic, the Bascom Palmer Eye Institute and the Ratner Children’s Eye Center.

The takeaway: The authors found that vision therapy/orthoptics was more effective than pencil push-ups or placebo vision therapy/orthoptics in reducing symptoms and improving signs of convergence insufficiency in children 9 to 18 years of age.
Read the trial (PDF)
The Scientific Basis for and Efficacy of Optometric Vision Therapy in Nonstrabismic Accommodative and Vergence Disorders

This article focuses on the scientific basis for vision therapy. It reviews studies that used objective recording techniques to assess the impact of vision therapy on the oculomotor system — the eye movement, focusing and tracking machinery itself, measured rather than reported.

Read the paper (PDF)

The Evidence

Research Summaries & Bibliographies

Collected reviews of the literature on vision, learning and the efficacy of vision therapy.

A Summary of Research and Clinical Studies on Vision and Learning

A listing of research reports and clinical studies on the relationship between vision and reading and learning ability, and on the effectiveness of vision therapy in treating learning-related vision problems.

Read the summary (PDF)
Research and Clinical Studies on Vision, Learning and Optometric Vision Therapy

This paper presents over 350 abstracts from 77 different journals across education, optometry, ophthalmology, neurology and psychology. It includes all of the works it found relating to vision and learning — including the papers arguing that there is no relationship between the two, of which there are only 15.

Read the bibliography (PDF)
Summary of Research on the Efficacy of Vision Therapy for Specific Visual Dysfunctions

This paper looks at studies in the largest areas of vision therapy treatment: accommodative and vergence anomalies — focusing and eye teaming.

The takeaway: According to the paper, the results of several large-sample retrospective studies provide compelling evidence of the effectiveness of vision therapy for these conditions.
Read the summary (PDF)

From Research to Your Family

What This Looks Like in Our Offices

The trial that gets cited most on this page tested office-based therapy with home reinforcement, in children roughly 9 to 18 years old, for one specific diagnosis. That is close to how our program runs — weekly in-office sessions at Coconut Creek, Boynton Beach, Boca Raton or West Palm Beach, with short daily activities at home between visits — and it is also a useful reminder of what research can and cannot promise. A study tells you what happened, on average, to a group of people who had a confirmed diagnosis. It does not tell you whether you or your child has that diagnosis.

That is the job of the evaluation. We measure eye teaming, focusing and tracking, tell you plainly what we found, and recommend therapy only when the findings call for it. If you are not sure whether it is worth booking, the symptom checklist takes about five minutes, and the problems we see most lists the everyday complaints that most often turn out to be visual.

Take the Symptom Checklist What an Evaluation Involves

Keep Reading

More Research & Plain-Language Guides

Does Vision Therapy Actually Work?

A plain-English look at what the evidence supports, where it is strongest, and where expectations should be set carefully.

Vision & Dyslexia Studies

38 peer-reviewed studies on vision, visual attention and reading difficulty, each with its citation and abstract.

Convergence Insufficiency

The condition the NEI trial studied — what it is, how it feels to a child, and how it is treated.

What a Developmental Evaluation Measures

The eye teaming, focusing and tracking tests that a 20/20 eye chart and a school screening never cover.

How Our Vision Therapy Program Works

Office-based therapy with home reinforcement — the format the research above examined.

Symptom Checklist

Five minutes of questions that tell you whether a developmental vision evaluation is worth booking.

Browse the Education Library →

Go Deeper

More on Whether Vision Therapy Works

The trials, the position statements and the honest limits of the evidence — including where the criticism has a point.

Research Narrows the Question. An Evaluation Answers It.

If reading, focusing or eye strain is a daily struggle in your house, a developmental vision evaluation will tell you whether the visual skills these studies measure are part of the picture — and what to do about it if they are.

Schedule an Evaluation About Vision Therapy