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Convergence Insufficiency Treatment Trial (CITT)

The recruitment status of this study is unknown. The completion date has passed and the status has not been verified in more than two years.
Verified October 2008 by National Eye Institute (NEI).
Recruitment status was:  Active, not recruiting
Information provided by:
National Eye Institute (NEI) Identifier:
First received: June 15, 2006
Last updated: March 24, 2010
Last verified: October 2008

The purposes of the CITT are:

  • To determine whether Home-based Pencil Push-up therapy, Home-based Pencil Push-ups with Computer Vision Therapy/Orthoptics or Office-based VT/Orthoptics more effective than placebo treatment, and whether there are differences between the three treatments in improving subject symptoms and signs.
  • To evaluate whether improvements in outcome measures are still present after one year of observation.

Condition Intervention Phase
Convergence Insufficiency
Binocular Vision Disorder
Behavioral: Home-based Pencil Push-Up Therapy
Behavioral: Home-based Pencil Push-ups with Computer Vision Therapy/Orthoptics
Behavioral: Office-based Vision Therapy/Orthoptics
Behavioral: Placebo Office-based Vision Therapy/Orthoptics
Phase 3

Study Type: Interventional
Study Design: Allocation: Randomized
Intervention Model: Parallel Assignment
Masking: Single Blind (Participant)
Primary Purpose: Treatment
Official Title: Convergence Insufficiency Treatment Trial (CITT)

Resource links provided by NLM:

Further study details as provided by National Eye Institute (NEI):

Primary Outcome Measures:
  • Measure of symptoms using a 15-item Convergence Insufficiency Symptom Survey [ Time Frame: 12 weeks ]

Secondary Outcome Measures:
  • Eyes' ability to converge when performing close work [ Time Frame: 12 weeks ]

Enrollment: 221
Study Start Date: July 2005
Estimated Study Completion Date: September 2009
Primary Completion Date: September 2008 (Final data collection date for primary outcome measure)
Intervention Details:
    Behavioral: Home-based Pencil Push-Up Therapy
    Exercise in which patients visually followed a small letter on a pencil as they moved the pencil closer to the bridge of their nose
    Behavioral: Home-based Pencil Push-ups with Computer Vision Therapy/Orthoptics
    Exercise in which patients visually followed a small letter on a pencil as they moved the pencil closer to the bridge of their nose combined with additional computer vision therapy
    Behavioral: Office-based Vision Therapy/Orthoptics
    Weekly hour-long sessions of office-based vision therapy with a trained therapist and performed at-home reinforcement exercises
    Behavioral: Placebo Office-based Vision Therapy/Orthoptics
    Vision activities designed to simulate office-based therapy
Detailed Description:

Convergence insufficiency is a prevalent and distinct binocular vision disorder. Typical symptoms include double vision, eyestrain, headaches, and blurred vision while reading. It affects approximately 5% of children in the United States, and may have a serious impact on an individual's performance in school, choice of jobs, and quality of life.

There is no consensus regarding the most effective treatment for convergence insufficiency. Two commonly prescribed treatments are home-based pencil push-up therapy and office-based vision therapy/orthoptics. Significant differences exist between these two treatment modalities in cost and number of office visits required, with pencil push-up therapy being less expensive and less time intensive. There have been no well-designed studies that have compared the effectiveness of these two treatments.

The Convergence Insufficiency Treatment Trial (CITT) is a prospective, masked, placebo-controlled, multi-center clinical trial in which 208 subjects between the ages of 9 to < 18 years will be randomly assigned to: 1) Home-based Pencil Push-Up Therapy, 2) Home-based Pencil Push-ups with Computer Vision Therapy/Orthoptics, 3) Office-based Vision Therapy/Orthoptics, or 4) Placebo Office-based Vision Therapy/Orthoptics. The primary outcome measure is a measure of symptoms using a 15-item survey, the CI Symptom Survey. Secondary outcome measures are two common clinical tests of the eyes' ability to converge when performing close work. Patients will be tested at the eligibility examination, and by masked examiners after 4, 8 and 12 weeks of treatment have been completed during the 12-week treatment phase. Long term follow-up will be assessed at 6 and 12 months after the completion of active treatment.


Ages Eligible for Study:   9 Years to 18 Years   (Child, Adult)
Sexes Eligible for Study:   All
Accepts Healthy Volunteers:   No

Inclusion Criteria:

  • Children between the ages of 9 and 17 years with symptomatic convergence insufficiency
  • Exophoria at near at least 4Δ greater than at far
  • Insufficient positive fusional convergence at near
  • A receded near point of convergence of ≥6 cm break
  • CI Symptom Survey score ≥16

Exclusion Criteria:

  • Previous treatment with office-based vision therapy/orthoptics or pencil push-ups
  • Systemic diseases known to affect accommodation, vergence and ocular motility
  • Developmental disability, mental retardation, attention deficit hyperactivity disorder (ADHD), or learning disability diagnosis that in the investigator's discretion would interfere with treatment
  Contacts and Locations
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Please refer to this study by its identifier: NCT00338611

United States, Alabama
University of Alabama at Birmingham School of Optometry
Birmingham, Alabama, United States, 35294
United States, California
Southern California College of Optometry
Fullerton, California, United States, 92093
Ratner Children's Eye Center
La Jolla, California, United States, 92093
United States, Florida
NOVA Southeastern University College of Optometry
Ft. Lauderdale, Florida, United States, 33328
Bascom Palmer Eye Institute
Miami, Florida, United States, 33136
United States, Minnesota
Mayo Clinic
Rochester, Minnesota, United States, 55905
United States, New York
State University of New York College of Optometry
New York, New York, United States, 10036
United States, Ohio
The Ohio State University College of Optometry
Columbus, Ohio, United States, 43210
United States, Pennsylvania
Pennsylvania College of Optometry
Philadelphia, Pennsylvania, United States, 19141
Sponsors and Collaborators
National Eye Institute (NEI)
Study Chair: Mitchell Scheiman, OD Pennsylvania College of Optometry
  More Information

Additional Information:
Publications automatically indexed to this study by Identifier (NCT Number):
Responsible Party: Mitchell Scheiman, OD, Pennsylvania College of Optometry Identifier: NCT00338611     History of Changes
Other Study ID Numbers: NEI-107
Study First Received: June 15, 2006
Last Updated: March 24, 2010

Keywords provided by National Eye Institute (NEI):
vision therapy
pencil push-up therapy

Additional relevant MeSH terms:
Ocular Motility Disorders
Vision Disorders
Central Nervous System Diseases
Nervous System Diseases
Cranial Nerve Diseases
Eye Diseases
Sensation Disorders
Neurologic Manifestations
Signs and Symptoms processed this record on May 25, 2017