NEI Clinical Studies

Vision In Preschoolers Study (VIP Study)

Purpose | Background | Description | Patient Eligibility | Recruitment Status | Current Status | Results | Publications | Resource Centers | NEI Representative

Purpose

To identify whether vision-screening tests can accurately identify preschool-aged children who would benefit from a comprehensive vision examination because of signs of amblyopia, strabismus, significant refractive error, and associated risk factors.

Background

Vision disorders are the fourth most prevalent class of disability in the United States and the most prevalent handicapping conditions in childhood. Early detection increases the likelihood of effective treatment and allows for actions to decrease the negative impact of the disorders. However, fewer than 15 percent of all preschool children receive an eye examination. Fewer than 22 percent of preschool children receive some type of vision screening. The methods for vision screening vary tremendously and the effectiveness of the methods in appropriately identifying children has not been documented. Amblyopia (2-5%), strabismus (3-4%), and significant refractive error (15-20%) are the prevalent and significant vision disorders of preschool children.

Description

The Vision In Preschoolers (VIP) Study is a multi-phased, multi-center, interdisciplinary, clinical study to evaluate the accuracy of screening tests used to identify preschool-aged children in need of further evaluation for vision disorders. The primary goal of the VIP Study is to determine whether there are tests or combinations of tests that can be used effectively to determine which preschoolers would benefit from a comprehensive eye examination to detect amblyopia, strabismus, significant refractive errors, and associated risk factors.

The VIP Study is designed in phases.

• Phase I (Years 1 and 2) was conducted over a two-year period. Phase I activities established which screening tests performed well when administered by licensed eye care professionals (optometrists and ophthalmologists experienced in the care of children) in a population of at least 2,000 Head Start preschoolers (at least 1,000 children per year) at high risk for the targeted vision disorders. Year 2 activities included evaluation of the performance of some commercially-available technology-based screening tests when administered by licensed eye care professionals. Year 2 activities also included evaluation of whether a selected set of tests was amenable to administration by lay screeners.
• Phase II activities will establish which screening tests perform well when administered by pediatric nurses and lay people on a high-risk population of at least 1,000 Head Start preschoolers. Each child will be tested twice with each screening test - once by a pediatric nurse and once by a lay screener. Tests selected for Phase II were determined by the outcome of Phase I.
• Phase III activities are currently under development. The category of screening personnel and the specific screening tests used in Phase III will be determined by the outcome of Phases I and II.

Description of Phase I

Phase I of the VIP Study provided estimates of the sensitivity and specificity of each of 11 screening tests and selected combinations of tests for detecting one or more of three targeted conditions (amblyopia, strabismus, and significant refractive error) and associated risk factors when the tests were conducted by licensed eye care professionals. Further, information on the most appropriate age-specific pass/fail criteria for tests was obtained during this phase.

In addition to completing the screening procedures, each child underwent a comprehensive eye examination by a licensed eye care professional who was masked to the results of the screening. Data collected during this eye examination was used as the gold standard with respect to the absence or presence of the conditions targeted for detection.

The 11 screening tests used in Phase I of the VIP Study were:

• Lea Symbols Visual Acuity Test (Precision Vision)
• HOTV Symbols Visual Acuity Test (Precision Vision)
• Random Dot E Stereoacuity Test (Stereo Optical)
• Stereo Smile Test II (Stereo Optical)
• Cover-Uncover Test
• Noncycloplegic Retinoscopy
• Retinomax 2 Autorefractor (Nikon)
• iScreen (Digital Vision Screening Technology)
• MTI Photoscreener (Medical Technologies Inc.)
• PowerRefractor II (plusoptiX)
• SureSight Vision Screener (Welch Allyn)

Additional tests administered by lay screeners in Year 2 were:

• Lea Symbols Visual Acuity Test (Precision Vision)
• Stereo Smile Test II (Stereo Optical)

Description of Phase II
In Phase II of the VIP Study, tests in need of further evaluation are being used by pediatric nurses and lay screeners to determine if the tests are amenable to administration by personnel with less training than licensed eye care professionals. Screenings are taking place in realistic screening environments.

The 4 screening tests being used in Phase II of the VIP Study are:

• Lea Symbols Visual Acuity Test (Good-Lite Company)
• Stereo Smile Test II (Stereo Optical)
• Retinomax 2 Autorefractor (Right Manufacturing Inc.)
• SureSight Vision Screener (Welch Allyn)

Each child is screened on each of these tests twice, once by a pediatric nurse screener and once by a lay screener. As in Phase I, all children completing the screening tests will undergo a comprehensive eye examination by a licensed eye care professional masked to the results of the screening. Data collected during the eye examination will be used as the gold standard with respect to the absence or presence of the conditions targeted for detection.

The results of Phase II will indicate which screening tests administered by pediatric nurses or lay screeners accurately identify children who would benefit from a comprehensive eye examination.

Patient Eligibility

Children enrolled in Head Start are eligible to participate in Phase II of the VIP Study.

Patient Recruitment Status

Ongoing for Phase II (2003-2004).

Current Status of Study

Phase I data collection is complete. In Year 1 of Phase I (2001-2002) 1,379 children were registered into VIP, 1,257 were screened and 1,195 received a comprehensive (Gold Standard) eye examination. In Year 2 of Phase I (2002-2003), 1,724 children were registered into VIP, 1,523 were screened and 1,471 received a comprehensive (Gold Standard) eye examination. Subject enrollment and data collection for Phase II are ongoing.

Results

The study results from Phase I showed that the 11 screening tests, when administered by highly trained personnel in a controlled environment, vary widely in their performance for detecting children who have amblyopia, strabismus, refractive error, and/or reduced visual acuity and who could benefit from a comprehensive eye examination.

Overview of Findings from Phase I

• With specificity set at 90%, sensitivities for detecting children with any VIP targeted condition were highest, and approximately equivalent for noncycloplegic retinoscopy (64%), Retinomax autorefractor (63%), SureSight Vision Screener (63%), and Lea symbols visual acuity testing (61%) among the 11 screening tests evaluated.
• Furthermore, when the sensitivity for detecting children with conditions considered the most important to detect was examined, these same 4 tests performed best: noncycloplegic retinoscopy (90%); Retinomax autorefractor (87%); SureSight Vision Screener (81%); and Lea symbols visual acuity testing (77%).
• Detection of children with amblyopia and detection of children with significant refractive error were most accurate when tests of refractive error were used, while most of the 11 tests showed similar accuracy for detection of children with strabismus.
• The tests that use static photorefraction (iScreen and MTI) were less accurate than noncycloplegic retinoscopy, the Retinomax autorefractor, and the SureSight Vision Screener.

General Summary of Findings

• When the best tests were used by highly skilled personnel, approximately two thirds of children with one or more VIP targeted disorders and 90% of those children with the most important conditions were identified, while referring 10% of normal children for an eye examination (90% specificity).

Publications

The Vision in Preschoolers Study Group: Preschool Visual Acuity Screening with HOTV and Lea Symbols: Testability and Between Test Agreement. Optom Vis Sci, in press.

The Vision in Preschoolers Study Group: Comparison of Preschool Vision Screening Tests as Administered by Licensed Eye Care Professionals in the Vision in Preschoolers Study. Ophthalmology 111: 637-650, 2004.

The Vision in Preschoolers Study Group: The Electronic Visual Acuity Tester: Testability of Preschool Children. Optom Vis Sci 81 (4): 238-243, 2004.

The Vision in Preschoolers Study Group: Testability of Preschoolers on Stereotests used to Screen Vision Disorders. Optom Vis Sci 80 (11): 753-757, 2003.

The Vision in Preschoolers Study Group: Threshold Visual Acuity Testing of Preschool Children using the Crowded HOTV and Lea Symbols Acuity Tests. J Pediatr Ophthalmol & Strabismus 7 (6): 396-399, 2003.

The Vision in Preschoolers Study Group: Visual Acuity Results in School-Aged Children and Adults: Lea Symbols Versus Bailey-Lovie Chart. Optom Vis Sci 80 (9): 650-654, 2003.

The Vision in Preschoolers Study Group: A Survey of Vision Screening Policy of Preschool Chldren in the United States. Survey of Ophthalmology 43 (5): 445-457, 1999.

The Vision in Preschoolers Study Group: Vision Screening of Preschool Children: Evaluation of the Past, Looking Toward the Future. Optom Vis Sci 75 (8): 571-584, 1998.

Schmidt PP: Screening for the Vision Problems of Young Children. In: Moore B, ed. Eye Car for Infants and Young Children. none Butterworth-Heinemann: 175-189, 1997.

Resource Centers

Chairperson's Office and Study Center
Beth Haas, Study Coordinator
The Ohio State University
College of Optometry
320 West Tenth Avenue
P.O. Box 182342
Columbus, OH 43218-2342
Telephone: (614) 247-6902
Fax: (614) 247-6907
E-mail: bhaas@optometry.osu.edu

Paulette P. Schmidt, O.D., M.S., Study Chairperson
The Ohio State University
College of Optometry
320 West Tenth Avenue
P.O. Box 182342
Columbus, OH 43218-2342
Telephone: (614) 292-3189
Fax: (614) 247-6907
E-mail: pschmidt@optometry.osu.edu

Coordinating Center
Agnieshka Baumritter, M.A., Project Director
Department of Ophthalmology
University of Pennsylvania
3535 Market Street
Suite 700
Philadelphia, PA 19104-3309
Telephone: (215) 615-1513
Fax: (215) 615-1531
E-mail: baumritt@mail.med.upenn.edu

Maureen G. Maguire, Ph.D., Director
Department of Ophthalmology
University of Pennsylvania
3535 Market Street
Suite 700
Philadelphia, PA 19104-3309
Telephone: (215) 615-1501
Fax: (215) 615-1531
E-mail: maguirem@mail.med.upenn.edu

NEI Representative

NEI Representative
Maryann Redford, D.D.S., M.P.H
Division of Extramural Research
National Eye Institute
National Institutes of Health
Suite 1300
5635 Fishers Lane, MSC 9300
Bethesda, MD 20892
Telephone: (301) 451-2020
Fax: (301) 402-0528
E-mail: maryann.redford@nei.nih.gov

Advisory Committee

Roy W. Beck, MD, PhD
Jaeb Center for Health Research
15310 Amberly Drive
Suite 350
Tampa, FL 33647
Telephone: (813) 975-8690
Fax: (813) 975-8761

Susan A. Cotter, OD
Southern California College of Optometry
2575 Yorbo Linda Blvd.
Fullerton, CA 92831
Telephone: (714) 449-7488
Fax: (714) 992-7846

Jonathan M. Holmes, MD
Department of Ophthalmology 7W
Mayo Clinic
200 1st Street SW
Rochester, MN 55905
Telephone: (507) 284-3760
Fax: (507) 284-8566

Sheila K. West, PhD
Wilmer Ophthalmological Institute
John Hopkins Hospital
129 Wilmer Building
600 North Wolfe Street
Baltimore, MD 21205
Telephone: (410) 955-2606
Fax: (410) 955-0096

Executive Committee

Elise Ciner, OD
Pennsylvania College of Optometry
1200 West Godfrey
Philadelphia, PA 19141
Telephone: (215) 276-6059
Fax: (215) 276-6196

Lynn Cyert, PhD, OD
Northeastern State University
College of Optometry
1001 N. Grand Avenue
Tahlequah, OK 74464
Telephone: (918) 456-5511, Ext. 4007
Fax: (918) 458-9603

Velma Dobson, PhD
Department of Ophthalmology
University of Arizona
655 N. Alvernon Way
Suite 108
Tuscon, AZ 85711
Telephone: (520) 322-3800, Ext. 238
Fax: (520) 321-3665

Marjean Taylor Kulp, OD, MS
The Ohio State University
College of Optometry
320 West Tenth Avenue
P.O. Box 182342
Columbus, OH 43218-2342
Telephone: (614) 688-3336
Fax: (614) 247-6907

Maureen G. Maguire, PhD
Department of Ophthalmology
University of Pennsylvania
3535 Market Street
Suite 700
Philadelphia, PA 19104-3309
Telephone: (215) 615-1501
Fax: (215) 615-1531

Bruce Moore, OD
New England College of Optometry
1255 Boylston Street
Boston, MA 02215
Telephone: (617) 236-6309
Fax: (617) 369-0198

Deborah Orel-Bixler, PhD, OD
School of Optometry
University of California, Berkeley
200 Minor Hall
Berkeley, CA 94720-2020
Telephone: (510) 642-2402
Fax: (510) 643-5109

Graham E. Quinn, MD
Division of Pediatric Ophthalmology
The Children's Hospital of Philadelphia
34th and Civic Center Boulevard
Wood Center, 1st Floor
Philadelphia, PA 19104
Telephone: (215) 590-4587
Fax: (267) 426-5015

Maryann Redford, DDS, MPH
Division of Extramural Research
National Eye Institute
National Institutes of Health
Suite 1300
5635 Fishers Lane, MSC 9300
Bethesda, MD 20892
Telephone: (301) 451-2020
Fax: (301) 402-0528

Paulette P. Schmidt, OD, MS
The Ohio State University
College of Optometry
320 West Tenth Avenue
P.O. Box 182342
Columbus, OH 43218-2342
Telephone: (614) 292-3189
Fax: (614) 247-6907

Janet Schultz, RN, MA, CPNP
Lourie Center Early Head Start
10738 Tucker Street
Beltsville, MD 20705
Telephone: (301) 937-1700, Ext. 11
Fax: (301) 937-1663

Last Updated: 4/1/2003