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. Author manuscript; available in PMC: 2010 Apr 1.
Published in final edited form as: Optom Vis Sci. 2009 Apr;86(4):357–363. doi: 10.1097/OPX.0b013e3181989252

Table 1.

Eligibility Criteria for Normal Binocular Vision Subjects.

Inclusion Criteria

  1. Age 9 to < 18 years

  2. Sex: either

  3. Ethnicity: any

  4. Best-corrected visual acuity ≥ 20/25 in both eyes at distance and near

  5. Appropriate refractive correction worn for at least 2 weeks (see below)

  6. Heterophoria at near between 2Δ esophoria and 8Δ exophoria

  7. Negative fusional vergence at near (greater than 7Δ BI-break/5Δ BI-recovery)

  8. Positive fusional vergence at near (greater than 10Δ BO-break/7Δ BO-recovery)

  9. NPC closer than 6.0 cm break

  10. Monocular amplitude of accommodation (greater than 15–0.25*age)

  11. Appreciation of random dot stereopsis using a 500 seconds of arc target

  12. Cycloplegic refraction within past 2 months

  13. Informed consent and willingness to participate in the study

Exclusion Criteria

  1. Previous treatment for CI (Any office- or home-based vision therapy or more than 2 weeks of pencil push-up therapy)

  2. Previous use of plus add at near or base-in prism

  3. Amblyopia (≥ 2 line difference in best-corrected visual acuity between the two eyes)

  4. Constant strabismus

  5. History of strabismus or refractive surgery

  6. Anisometropia ≥ 2.0D spherical equivalent

  7. High refractive error: Myopia ≥ 6.00D sphere (in any meridian); Hyperopia ≥ 5.00D sphere (in any meridian); Astigmatism ≥ 4.00D

  8. Vertical heterophoria greater than 1Δ

  9. Diagnosed with multiple sclerosis, Grave’s thyroid disease, myasthenia gravis, diabetes, or Parkinson’s disease

  10. Manifest or latent nystagmus

  11. Developmental disability, mental retardation, ADHD or learning disability that, in the investigators opinion, would interfere with the child’s ability to respond to survey items