Previous research in English has suggested that reading rate predictions can be improved considerably by taking average word length into account. In the present study, we investigated whether the same regularity holds for Dutch. The Dutch language is very similar to English, but words are on average half a letter longer: 5.1 letters per word (in non-fiction) instead of 4.6. We collected reading rates of 62 participants reading 12 texts with varying word lengths, and examined which change in the English equation accounts for the Dutch findings. We observed that predictions were close to the best fitting curve as soon as the average English word length was replaced by the average Dutch word length. The equation predicts that Dutch texts with an average word length of 5.1 letters will be read at a rate of 238 word per minute (wpm). Texts with an average word length of 4.5 letter will be read at 270 wpm, and texts with an average word length of 6.0 letters will be read at a rate of 202 wpm. The findings are in line with the assumption that the longer words in Dutch do not slow down silent reading relative to English and that the word length effect observed in each language is due to word processing effort and not to low-level, visual factors.

以前的英语研究表明，通过考虑平均字长，可以大大提高阅读率预测。在本研究中，我们调查了荷兰语是否存在相同的规律。荷兰语与英语非常相似，但单词平均长半个字母：每个单词 5.1 个字母（非小说）而不是 4.6 个。我们收集了 62 名参与者阅读 12 篇不同字长文本的阅读率，并检查了英语方程的哪些变化可以解释荷兰语的发现。我们观察到，一旦平均英语单词长度被平均荷兰语单词长度取代，预测就会接近最佳拟合曲线。该等式预测平均字长为 5.1 个字母的荷兰语文本将以每分钟 238 个字 (wpm) 的速度阅读。平均字长为 4.5 个字母的文本将以 270 wpm 的速度阅读，而平均字长为 6.0 个字母的文本将以 202 wpm 的速度阅读。研究结果符合以下假设：相对于英语，荷兰语中较长的单词不会减慢默读速度，并且在每种语言中观察到的词长效应是由于文字处理工作而不是低级视觉因素造成的。