Objective: This study was performed in order to compare the lexicosyntactic readability, and the information density in the informed consent forms used in biomedical research, in comparison with standard scientific texts dedicated to the general population. In addition, we studied whether there is a correlation between information readability and density.
Methods: Fifteen informed consent forms, 6 articles from "Sciences et Avenir" and 6 articles from "Sciences et Vie Junior" were analyzed. The lexicosyntactic readability was calculated using the Flesh score, and the information density using the number of information bits related to the number of words.
Results: The lexicosyntactic readability was lower in the informed consent forms (25, 17-32) compared with "Sciences et Avenir" (32, 29-38), but even higher in "Sciences et Vie Junior" (42, 38-57). Conversely, the information density was similar in "Sciences et Vie Junior" (0.24, [0.21-0.27]) and the informed consent forms (0.24, [0.22-0.26]), but higher in "Sciences et Avenir" (0.32, [0.26-0.38]).
Conclusion: Informed consent forms are less readable, but paradoxically less dense than scientific papers dedicated to the general population. There is no correlation between density and readability.