Utilizing Basic Screening Principles in the Design and Evaluation of Vision Screening Programs

Abstract

Basic screening principles are often overlooked when vision screening programs are designed and evaluated. These principles are reviewed with examples of the method used to determine the sensitivity, specificity, positive and negative predictive values of screening tests/programs.

The design and implementation of the Enhanced Vision Screening Program (EVSP), a population based vision screening program targeted to pre-school children, and successful in capturing 99.5 percent of the target population in the province of Nova Scotia is introduced. Preliminary outcome data for 1988 is presented, revealing a positive predictive value of 72 percent for this group. The costs of the Program are reviewed. The parameters of the EVSP with respect to basic screening principles are discussed.

• vision screening
• amblyopia screening
• strabismus screening
• children's vision
• stereopsis
• visual acuity