One hundred and twenty-six unselected consecutive single-vision prescriptions were included in this study. All powers were rounded off to onehalf diopter steps by reducing every meridional measurement +0.25 if it was not already in a half-diopter step. Ninety-one patients could subsequently be reached and queried as to their satisfaction with their new spectacles. Six of 15 patients who had neither lens changed expressed some dissatisfaction, five of 31 patients who had just one lens changed expressed some dissatisfaction, and ten of 45 patients who had both lenses changed expressed some dissatisfaction. Of the ten patients who were dissatisfied enough with their prescriptions to return them, four had not been rounded off in either lens.
Appleton B. Ophthalmic Prescription in Half-Diopter IntervalsPatient Acceptance. Arch Ophthalmol. 1971;86(3):263-267. doi:10.1001/archopht.1971.01000010265005