Development of a reading difficulty questionnaire for adolescents in Japanese

Dyslexia is a neurodevelopmental disorder which occurs in childhood but continues to influence academic and occupational function in adulthood. Recently, a Japanese dyslexia questionnaire and diagnostic procedure was established for primary school children. However, there is currently no procedure for the diagnosis or screening of dyslexia in individuals at or above junior high school age; accordingly, we aimed to develop a questionnaire to screen for reading difficulties in those individuals.

A questionnaire with various candidate items was developed from two English questionnaires, one Japanese questionnaire, and newly devised items focusing on the Japanese writing system and the most appropriate 28 items were selected. In total, 462 adults and 127 junior high to high school students were enrolled. Of those, 191 participants also took part in reading tests. After the exploratory factor analysis, reliability and validity were evaluated using the above control participants and 12 adolescents with dyslexia.

The questionnaire included three factors, i.e., silent reading sub-scale (four items), writing sub-scale (four items), and aloud reading sub-scale (three items). Five were newly devised items focusing on the Japanese writing system. Cronbach's alphas of the three factors were 0.706, 0.638, and 0.568, respectively, and the interclass correlation coefficients (2,1) were 0.743, 0.609, and 0.695, respectively. The silent reading and aloud reading sub-scales were positively correlated with word, non-word, and passage reading time.

The newly developed questionnaire correlated well with actual reading performance and may be used to screen reading difficulty in Japanese individuals at or above junior high school age.