Wang Chen-xiao, Liu Zhi-hui, Gao Ji-tuo, Guo Ying-xuan, He Ji-cang, Qu Jia, Lü Fan
Eye Hospital, Wenzhou Medical College, Wenzhou 350027, China.
Zhonghua Yan Ke Za Zhi. 2013 Jun;49(6):536-40.
Reading is a visual function human being used to understand environmental events based on writing materials. This study investigated the feasibility of reading visual acuity chart in assessment of reading ability by analysis of the key factors involved in the design of the visual acuity chart.
The reading level was determined as grade 3 primary school with Song as the font and 30 characters included in the sentences. Each of the sentences consisted of 27 commonly-used Chinese characters (9 characters between any two punctuations) and 3 punctuations. There were no contextual clues between the 80 sentences selected. The characters had 13 different sizes with an increment of 0.1 log unit (e.g.1.2589) and 2.5 pt was determined as the critical threshold. Readable test for visual target was followed as (1) 29 candidates with a raw or corrected visual acuity (VA)of at least 1.0 were selected to read 80 selected sentences with the size of characters of 2.5 pt at a distance of 40 cm, (2) the time used for reading with the number of characters wrongly read was recorded, (3) 39 sentences were selected as visual targets based on reading speed, effective reading position and total number of character strokes, (4) The 39 selected sentences were then randomly divided into 3 groups with no significant difference among the groups in the 3 factors listed at (3) with paired t-test.
This reading visual chart was at level of Grade 3 primary school with a total stroke number of 165-210(Mean 185 ± 10), 13 font sizes a 0.1 log unit increment, a song pattern and 2.5 pt as the critical threshold. All candidates achieved 100% correct in reading test under 2.5 pt with an effective reading speed as 120.65-162 wpm (Mean 142.93 ± 11.80) and effective reading position as 36.03-61.48(Mean 48.85 ± 6.81). The reading test for the 3 groups of sentences showed effective reading speed as (142.49 ± 12.14) wpm,(142.86 ± 12.55) wpm and (143.44 ± 11.63) wpm respectively(t1-2 = -0.899, t2-3 = -1.295, t1-3 = -1.435). The reading position was 48.55 ± 6.69, 48.99 ± 7.49 and 49.00 ± 6.76, respectively(t1-2 = -1.019, t2-3 = -0.019, t1-3 = -0.816). The total number of character strokes was 185.54 ± 7.55, 187.69 ± 13.76 and 182.62 ± 8.17, respectively(t1-2 = 0.191, t2-3 = 1.385, t1-3 = 1.686).
A practical design of the Chinese reading visual chart should consider size, increment, legibility in selection of reading sentences. Reading visual acuity, critical threshold and effective reading speed could be used to express the reading visual function.
阅读是人类基于书面材料来理解环境事件的一种视觉功能。本研究通过分析视力表设计中的关键因素，探讨阅读视力表在评估阅读能力方面的可行性。
将阅读水平设定为小学三年级，字体为宋体，句子包含30个字符。每个句子由27个常用汉字（任意两个标点之间9个汉字）和3个标点组成。所选的80个句子之间没有上下文线索。汉字有13种不同大小，以0.1对数单位递增（如1.2589），并将2.5磅确定为临界阈值。视觉目标的可读性测试如下：（1）选择29名裸眼或矫正视力（VA）至少为1.0的受试者，在距离40厘米处阅读字符大小为2.5磅的80个选定句子；（2）记录阅读所用时间及读错的字符数；（3）根据阅读速度、有效阅读位置和总笔画数选择39个句子作为视觉目标；（4）将选定的39个句子随机分为3组，这3组在（3）中列出的3个因素上无显著差异，采用配对t检验。
本阅读视力表为小学三年级水平，总笔画数为165 - 210（平均185±10），有13种字体大小以0.1对数单位递增，为宋体样式，2.5磅为临界阈值。所有受试者在2.5磅以下的阅读测试中正确率均达到100%，有效阅读速度为120.65 - 162词/分钟（平均142.93±11.80），有效阅读位置为36.03 - 61.48（平均48.85±6.81）。3组句子的阅读测试显示有效阅读速度分别为（142.49±12.14）词/分钟、（142.86±12.55）词/分钟和（143.44±11.63）词/分钟（t1 - 2 = -0.899，t2 - 3 = -1.295，t1 - 3 = -1.435）。阅读位置分别为48.55±6.69、48.99±7.49和49.00±6.76（t1 - 2 = -1.019，t2 - 3 = -0.019，t1 - 3 = -0.816）。总笔画数分别为185.54±7.55、187.69±13.76和182.62±8.17（t1 - 2 = 0.191，t2 - 3 = 1.385，t1 - 3 = 1.686）。
中文阅读视力表的实用设计应考虑字号、递增幅度、阅读句子选择的易读性。阅读视力、临界阈值和有效阅读速度可用于表达阅读视觉功能。
