The Impact of Uncorrected/Under-Corrected Refractive Error on Drivers: A Systematic Review
Kovin Naidoo, Nyika Mtemeri, Iris Gordon, Peter Clarke-Farr, Percy Mashige, Jyoti Naidoo
Commissioned by the Vision Impact Institute
Decreased visual acuity in drivers, resulting from uncorrected refractive error (URE), may have detrimental impacts on specific driving tasks.
The objective of this systematic review is to summarise relevant evidence investigating the negative impact(s) of uncorrected refractive error and the impact of correcting refractive error on licensed drivers 16 years and older, globally.
It systematically searched 12 databases and the reference lists of retrieved studies. The methodology employed adhered to the PRISMA statement. Consolidated Standards of Reporting Trials (CONSORT) Guidelines and the Critical Appraisal Skills Programme (CASP) tools were used to assess the quality of full text articles in the review synthesis. We used a descriptive narrative to report the findings of the review.
Outcomes measures included, Psychosocial (behavioural, well-being and quality of life), and driving performance (frequency of road accidents/ crashes, reduced driving distance and frequency, driving distance and frequency, driving cessation-including impacts on social/ emotional development, sign recognition, night driving) and impact of RE correction (sign recognition, viewing odometer, night/ day time driving).
The search yielded 12164 studies, of which 9 met the inclusion criteria. Studies included 6 cross-sectional and 3 case control designs. The lack of randomised control trials (RCTs) in the determination of the impact of refractive error reduces the granularity of the data that is presented. The three case control studies provides a strong case for refractive error blur impacting on driving performance. The simulation of blur, while it can be argued in not a precise replication of the reality of uncorrected refractive error, addressed two significant issues. These are the limitations of self-reported accident and driving experience data and the ethical dilemma that arises from asking subjects to drive uncorrected.