Which VA test do you use in practice? What are its drawbacks? What are its benefits?
I use a reversed Snellen chart with a range of 6/60 to 6/5 at 3 metres with a mirror for all but very young patients for whom I use the Keeler (Glasgow) Acuity Cards and for the very very young Cardiff acuity cards. Here, I will concentrate on the drawbacks of the Snellen chart for which there are many.
Nevertheless, in my experience it is still widely used in many countries. There are very few letters for patients with poor visual acuity; some patients learn the limited letter sequence and achieve better visual acuities than they should; children can become confused by the mirror and simply turnaround and read from the chart just above them; some letters are more difficult/easier to see than others because of the letter structure.
Benefits; low cost; easy for patients to use; recognised system for visual acuity determination; useful to gauge success or otherwise of my refraction; useful for detecting amblyopia and a whole range of ocular/ pathway disease; works for most people examined in primary care optometry practice.