Abstract
Purpose: :
This paper will report the number and prevalence of the color vision defects identified and the sensitivities and specificities of the color vision screening tests performed on USAF pilot applicants from 01 Jan 1999 through 31 Jul 2003 at Brooks City–Base, Texas.
Methods: :
10760 eyes were screened with the PIP–1, PIP–2, PIP–3, and F2. Eyes failing any one of these tests underwent a complete ophthalmic examination and additional color vision testing (Falant, D–15, FM–100, anomaloscope). All candidates had previously passed a single PIP–1 screening test as part of preliminary medical screening programs.
Results: :
Of the 10760 screened eyes, 141 color deficient eyes were identified. The following are the number and the prevalence of color vision defects identified: protanomalous– 38, 0.35%; deuteranomalous– 74, 0.69%; tritanomalous– 5, 0.05; protanopic– 4, 0.04%; deuteranopic– 16, 0.15%; and tritanopic– 4, 0.04%. The following are the sensitivities and specificities, respectively, of the color vision tests employed: PIP–1 (53.9%, 90.5%), PIP–2 (62.4%, 76.2%), PIP–3 (48.9%, 19.0%), F–2 (70.2%, 90.5%), Falant (44.0%, 81.0%), FM–100 (36.9%, 85.7%), and D–15 (19.1%, 100.0%).
Conclusions: :
The previous United Air Force Color Vision Screening program, only the PIP–1, would have failed to identify nearly 47% of the color deficient eyes identified by the battery of screening color vision tests currently used at Medical Flight Screening (PIP–1, PIP–2, PIP–3, F–2). The best individual color vision screening tests was the F–2, identifying more than 70% of the color deficient eyes. Employing a battery of screening tests increases the sensitivity of the color vision screening program, but also increases the false positive rate. For example, the battery of PIP–1, PIP–2, PIP–3, and F–2 had false positive rate of 90.5%, largely due to the PIP–3's false positive rate of 90.5%. Eliminating the PIP–3 from the battery reduces the false positive rate to 23.8% with a sensitivity of 90.8%. Using only the PIP–1 and the F–2 yields a sensitivity of 85.1% and a 9.5% false positive rate. Like any screening program the benefit of an increased sensitivity must be weighed against the cost of an increased false positive rate. The results of this paper and future similar studies have the potential to aid in the development of effective color vision screening protocols for both military and civilian aviation medical screening programs.