Original article Intelligence test at preschool-age predicts reading difficulty among school-aged very low birth weight infants in Japan Akihito Takeuchi a,⇑ , Tatsuya Ogino b , Tatsuya Koeda c , Makio Oka d , Takashi Yorifuji e , Toshimitsu Takayanagi f , Kazuo Sato g , Noriko Sugino h , Motoki Bonno h , Makoto Nakamura a , Misao Kageyama a a Department of Neonatology, Okayama Medical Center, National Hospital Organization, Okayama, Japan b Department of Children Studies, Faculty of Children Studies, Chugokugakuen University, Okayama, Japan c Department of Psychosocial Medicine, National Center for Child Health and Development, Tokyo, Japan d Department of Child Neurology, Okayama University Graduate School of Medicine, Dentistry and Pharmaceutical Science, Okayama, Japan e Department of Human Ecology, Okayama University Graduate School of Environmental and Life Science, Okayama, Japan f Department of Pediatrics, Saga Hospital, National Hospital Organization, Saga, Japan g Department of Pediatrics, Kyushu Medical Center, National Hospital Organization, Fukuoka, Japan h Department of Neonatology, Mie Chuo Medical Center, National Hospital Organization, Tsu, Japan Received 9 January 2018; received in revised form 2 May 2018; accepted 8 May 2018 Abstract Objective: To elucidate whether the results of an intelligence test at preschool age are predictive of reading difficulty (RD) at school age among very low birth weight infants (VLBWI). Methods: Subjects were 48 Japanese children whose birth weight was <1500 g and who regularly visited a follow-up clinic. All subjects completed the Wechsler Intelligence Scale for Children-III (WISC-III) during the last grade of kindergarten, and four read- ing tasks during the second to fourth grade of elementary school. All participants had a full-scale intelligence quotient score of 85 or higher. Subjects with a standard deviation reading time score greater than 2.0 in two or more tasks were considered to have RD. We evaluated the associations between each WISC-III score and RD using logistic regression analyses. Furthermore, we performed receiver operating characteristic (ROC) analysis to determine a cutoff WISC-III score predictive of RD. Results: In the mutually-adjusted model, the adjusted odds ratio per 1 score increase of freedom from distractibility (FD) was 0.832 (95% confidence interval: 0.720–0.962). In the ROC analysis, an FD score of <95.5 was chosen as the cutoff value for predict- ing RD (sensitivity, 0.77; specificity, 0.74). Conclusion: The present study indicated that a lower FD score at preschool age, which was associated with deficits in verbal working memory and attention, is a risk factor for RD at school age among Japanese VLBWI. Further investigation is desired to clarify the cognitive deficits underlying RD in Japanese-speaking preterm children, and to establish appropriate interventions for these children. Ó 2018 The Japanese Society of Child Neurology. Published by Elsevier B.V. All rights reserved. Keywords: Very low birth weight infant; VLBW; Preterm; Reading difficulty; Dyslexia; Japanese; Verbal working memory; Attention https://doi.org/10.1016/j.braindev.2018.05.002 0387-7604/Ó 2018 The Japanese Society of Child Neurology. Published by Elsevier B.V. All rights reserved. ⇑ Corresponding author at: Department of Neonatology, Okayama Medical Center, National Hospital Organization, 1711–1 Tamasu, Kita-ku, Okayama 701–1192, Japan. E-mail address: gmd18025@s.okayama-u.ac.jp (A. Takeuchi). www.elsevier.com/locate/braindev Brain & Development xxx (2018) xxx–xxx Please cite this article in press as: Takeuchi A et al. Intelligence test at preschool-age predicts reading difficulty among school-aged very low birth weight infants in Japan. Brain Dev (2018), https://doi.org/10.1016/j.braindev.2018.05.002