The correct addition for near vision in presbyopia depends primarily on the amount of available accommodation and secondarily on the selection of the best fixed distance for the near work.
In correcting presbyopia, it has been customary among ophthalmologists to give the patient only one test, that is, to determine the addition with which the patient "reads best" or feels most comfortable at the desired distance on the Prince rule. In ophthalmology one has at least three common methods of determining the correct distance refraction, or punctum remotum : (1) retinoscopic examination with cycloplegia, (2) trial case determinations with cycloplegia and (3) the postcycloplegia test. I recommend three methods for measuring the near point refraction, punctum proximum, or accommodation. I believe that the near point in the refraction of presbyopia is as important as the far point. Each of my three tests depends on distinctly different types of thresholds of visual
SLATAPER FJ. ACCOMMODATION OF PRESBYOPIA AND ITS CORRECTION. Arch Ophthalmol. 1945;34(5):389–397. doi:10.1001/archopht.1945.00890190391006