A New Parameter for the Assessment of Distance Visual Capacity: the Critical Visual Acuity (CVA)

"The VA of all participants will be evaluated by counting the smallest line that can be read within a time duration greater than or equal to the average reading time of the larger lines minus 2.58 times the SD of the reading time of these lines.~In clinical practice, the VA is the common parameter of VA adding a tolerant time limit to clearly determine the end of the test."

"The CVA of all participants will be evaluated by counting the smallest line that can be read within a time duration greater than or equal to the average reading time of the larger lines minus 1.96 times the SD of the reading time of these lines.~In clinical practice, the CVA is the minimum VA that can be read in maximal speed."