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The convergence insufficiency treatment trial: design, methods, and baseline data

1

  • 1Pennsylvania College of Optometry, 1200 West Godfrey Ave, Philadelphia, PA 19141, USA. mscheiman@pco.edu

Ophthalmic Epidemiology
|February 27, 2008
PubMed

Insights

The Convergence Insufficiency Treatment Trial (CITT) established a robust methodology for evaluating treatments for convergence insufficiency in children. Baseline data from 221 children were collected to define the clinical profile of participants.

Area of Science:

  • Ophthalmology
  • Pediatric Optometry
  • Clinical Trial Design

Background:

  • Convergence insufficiency (CI) is a common binocular vision disorder affecting children.
  • Previous treatment evaluations lacked large-scale, placebo-controlled, randomized clinical trial designs.

Purpose of the Study:

  • To describe the design and methodology of the Convergence Insufficiency Treatment Trial (CITT).
  • To report the clinical and demographic characteristics of children enrolled in the CITT.

Main Methods:

  • Prospective randomization of children aged 9-17 into four treatment groups: home-based pencil push-ups, home-based computer therapy, office-based therapy with home reinforcement, and office-based placebo.
  • Outcome measures included the Convergence Insufficiency Symptom Survey (CISS) score, near point of convergence (NPC), and positive fusional vergence.
  • Data collected at baseline, 12 weeks post-treatment, and 6 and 12 months post-treatment.

Main Results:

  • The CITT enrolled 221 children with symptomatic CI, mean age 12.0 years.
  • Baseline clinical profile: 9Δ exophoria at near, 2Δ exophoria at distance, CISS score 30, NPC 14 cm, near positive fusional vergence break 13Δ.
  • No significant baseline differences observed between the four treatment groups.

Conclusions:

  • The CITT employed rigorous design features: formal outcome definitions, standardized protocols, placebo arm, masked examinations, and CISS score.
  • The reported baseline data characterize the cohort for this pivotal CI study.
Abstract

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