Mansfield J S, Atilgan N, Lewis A M, Legge G E
Department of Psychology, SUNY College at Plattsburgh, Plattsburgh, NY, USA.
Department of Psychology, University of Minnesota, Minneapolis, MN, USA.
Vision Res. 2019 May;158:11-18. doi: 10.1016/j.visres.2019.01.010. Epub 2019 Feb 18.
The MNREAD chart consists of standardized sentences printed at 19 sizes in 0.1 logMAR steps. There are 95 sentences distributed across the five English versions of the chart. However, there is a demand for a much larger number of sentences: for clinical research requiring repeated measures, and for new vision tests that use multiple trials at each print size. This paper describes a new sentence generator that has produced over nine million sentences that fit the MNREAD constraints, and demonstrates that reading performance with these new sentences is comparable to that obtained with the original MNREAD sentences. We measured reading performance with the original MNREAD sentences, two sets of our new sentences, and sentences with shuffled word order. Reading-speed versus print-size curves were obtained for each sentence set from 14 readers with normal vision at two levels of blur (intended to simulate acuity loss in low vision) and with unblurred text. We found no significant differences between the new and original sentences in reading acuity and critical print size across all levels of blur. Maximum reading speed was 7% slower with the new sentences than with the original sentences. Shuffled sentences yielded slower maximum reading speeds and larger reading acuities than the other sentences. Overall, measures of reading performance with the new sentences are similar to those obtained with the original MNREAD sentences. Our sentence generator substantially expands the reading materials for clinical research on reading vision using the MNREAD test, and opens up new possibilities for measuring how text parameters affect reading.
MNREAD视力表由按0.1对数最小分辨角（logMAR）步长的19种字号印刷的标准化句子组成。该视力表的五个英文版本共有95个句子。然而，对于句子数量有更多需求：对于需要重复测量的临床研究，以及对于在每个字号下使用多次试验的新视力测试。本文描述了一种新的句子生成器，它生成了超过900万个符合MNREAD限制的句子，并证明使用这些新句子的阅读表现与使用原始MNREAD句子所获得的表现相当。我们用原始MNREAD句子、两组我们的新句子以及词序打乱的句子来测量阅读表现。从14名视力正常的读者那里，针对每个句子集，在两种模糊程度（旨在模拟低视力中的视力丧失）以及文本未模糊的情况下，获取阅读速度与字号的曲线。我们发现在所有模糊程度下，新句子和原始句子在阅读敏锐度和临界字号方面没有显著差异。新句子的最大阅读速度比原始句子慢7%。打乱顺序的句子产生的最大阅读速度比其他句子慢，且阅读敏锐度更高。总体而言，使用新句子的阅读表现测量结果与使用原始MNREAD句子所获得的结果相似。我们的句子生成器极大地扩展了使用MNREAD测试进行阅读视力临床研究的阅读材料，并为测量文本参数如何影响阅读开辟了新的可能性。
