Career preferences, aptitudes, and test scores. A further investigation by the same authors (Klare et al. 1955c) looked into the effect of career aptitude and preferences on immediate retention. As expected, the subjects with higher degree of mechanical and clerical aptitude showed consistently higher retention on test scores. There were no significant relationships, however, between career preferences and retention.

Interest, Prior Knowledge, Readability and Comprehension A study (Klare 1976) of the experiments on the effects of using formulas to revise texts showed how different levels of motivation and reading ability can skew the results. It also indicated that the readability of a text is more important when interest is low than when it is high. The study by Fass and Schumacher (1978) supports this claim.

Woern (1977) later showed that prior knowledge and beliefs about the world affected comprehension significantly. Pearson, Hanson, and Gordon (1979) discovered significant effects of prior knowledge on the comprehension of children reading about spiders. Spilich, Vesonder, Chiesi, and Voss (1979) found that subjects having more knowledge about baseball remembered more information about a baseball episode. Chiesi, Spilich, and Voss (1979) found that high-knowledge subjects had better recognition, recall, and anticipation of goal outcomes than did low-knowledge subjects.

Entin and Klare (1985) took up the interaction between the readability of the text and the prior knowledge and interest of the readers. The study used 66 students enrolled in introductory psychology courses at Ohio University. They were first tested with the Nelson-Denny Reading Test to determine reading skills. They were then given a questionnaire on their interest in selected topics and a questionnaire on their prior knowledge of the terminology used in the test passages. For test passages, they used 12 selected passages from the World Book Encyclopedia, six high-interest passages, and six low-interest ones. The passages were re-written and normed by judges for content at the 12^th and 16^th-grade levels, resulting in 24 passages for the experiment. Then, two cloze tests were made of each passage, resulting in 48 test passages.

This study confirmed that easier readability of a text has more benefits for those of less knowledge and interest than those of more. Advanced knowledge of a subject can "drown out" the effects of an otherwise difficult text.

This study also suggested that when reader interest is high, comprehension is not improved by writing the material below, rather than at, the grade level of the readers. When interest is low, however, comprehension is improved by writing the materials below, rather than at, the reading level of the readers. Comprehension was improved when the materials are written at the reading levels of all readers rather than above those levels.

Reading efficiency

While early studies used reader comprehension as a measure of readability, new studies were looking at other measures such as:

• Readership
• Reading persistence (or perseverance)
• Reading efficiency

Readability and reader persistence Several studies in the field of journalism found a significant relationship between reader persistence and readability. Some used split runs of newspapers to see the effects of improved readability on wide audiences.