Population‐based assessment of sensitivity and specificity of a pinhole for detection of significant refractive errors in the community

Abstract

Background: Measurements of refractive errors through subjective or automated refraction are not always possible in rapid assessment studies and community vision screening programs; however, measurements of vision with habitual correction and with a pinhole can easily be made. Although improvements in vision with a pinhole are assumed to mean that a refractive error is present, no studies have investigated the magnitude of improvement in vision with pinhole that is predictive of refractive error. The aim was to measure the sensitivity and specificity of 'vision improvement with pinhole' in predicting the presence of refractive error in a community setting. Methods: Vision and vision with pinhole were measured using a logMAR chart for 488 of 582 individuals aged 15 to 50 years. Refractive errors were measured using non-cycloplegic autorefraction and subjective refraction. The presence of refractive error was defined using spherical equivalent refraction (SER) at two levels: SER greater than ± 0.50 D sphere (DS) and SER greater than ±1.00 DS. Three definitions for significant improvement in vision with a pinhole were used: 1. Presenting vision less than 6/12 and improving to 6/12 or better, 2. Improvement in vision of more than one logMAR line and 3. Improvement in vision of more than two logMAR lines. Results: For refractive error defined as spherical equivalent refraction greater than ± 0.50 DS, the sensitivities and specificities for the pinhole test predicting the presence of refractive error were 83.9 per cent (95% CI: 74.5 to 90.9) and 98.8 per cent (95% CI: 97.1 to 99.6), respectively for definition 1. Definition 2 had a sensitivity 89.7 per cent (95% CI: 81.3 to 95.2) and specificity 88.0 per cent (95% CI: 4.4 to 91.0). Definition 3 had a sensitivity of 75.9 per cent (95% CI: 65.5 to 84.4) and specificity of 97.8 per cent (95% CI: 95.8 to 99.0). Similar results were found with spherical equivalent refraction greater than ±1.00 DS, when tested against the three pinhole-based definitions. Conclusion: Refractive error definitions based on improvement in vision with the pinhole shows good sensitivity and specificity at predicting the presence of significant refractive errors. These definitions can be used in rapid assessment surveys and community-based vision screenings.

Uncorrected refractive errors for distance among the residents in 'homes for the aged' in South India–The Hyderabad Ocular Morbidity in Elderly Study (HOMES)

“…Another limitation of those studies including the rapid assessment studies is the use of pinhole‐based visual acuity improvement as a surrogate measure for URE 25‐27 . Though the pinhole is found to be sensitive to detect URE, 28 it is subject to certain limitations 29 . Another challenge in comparing the results across studies is the criteria used to define URE.…”

Prevalence of refractive errors, uncorrected refractive error, and presbyopia in adults in India: A systematic review

“…However, considering the logistics, time, and resource requirements for population-based assessments, pinhole assessment with the VA cut-point of <6/18 is more convenient to use in rapid assessment surveys and community-based vision screenings. [33] One study by Marmamula and colleagues published in 2009 used the cut-point of 6/12 rather than the WHO cut-point of 6/18. [10] This study was not included in the pooled estimates as the majority of studies used 6/18 as the cut-point, which is the WHO definition.…”

Accuracy of autorefraction in an adult Indian population

“…Moreover, refractive error is still a leading cause of low vision and blindness even among adults, and thus a comprehensive program for eye disease screening would do well to include at least some testing for refractive error [ 23 ]. Less expensive instruments like the pinhole occluder have been shown to be sensitive and specific for detection of refractive error, so it may not be necessary to include an expensive electronic device in screening programs [ 24 , 25 ]. On the other hand, older adults sometimes have difficulty navigating the pinhole test, whereas the autorefractor does not require much cooperation to provide a result.…”