Textbook selection is based on a number of criteria, one of which may be reading level. METHOD: We searched the literature to find an appropriate method for reading-level assessment and then evaluated 11 respiratory therapy textbooks for average reading-level and internal reading-level variation by the Luiten, Ames, Bradley Variation Method (LAB), which is based on the Fry Readability Model. The LAB is a validated method that employs 12 100-word samples from each book evaluated. We counted syllables and sentences in each sample, computed the mean and standard deviation (SD) of each, multiplied SD by a constant based on t distribution values, and plotted a zone that allows prediction of the average reading level and the internal variation in reading level of 80% of the book. RESULTS: Nine of the books had an average reading level of Grade 17, one was at Grade 16, and one at Grade 14. All books had internal grade-level variations, of as little as 2 years to as much as 10 years. CONCLUSION: This study suggests that some respiratory therapy textbooks in common use are written at a high grade level and have marked grade-level variability within the text. Students may have difficulty comprehending the content of textbooks written at a level beyond their ability. Comprehension may be improved if students are required to master terminology prior to respiratory therapy classwork and if they are required to outline and/or rewrite reading assignments. Authors who are writing introductory texts should use shorter sentences and simpler language wherever possible.
Watson et al. (Tue,) studied this question.