Abstract
Nonverbal IQ (NVIQ) was examined in 84 individuals with autism spectrum disorder (ASD) followed from age 2 to 19. Most adults who scored in the range of intellectual disability also received scores below 70 as children, and the majority of adults with scores in the average range had scored in this range by age 3. However, within the lower ranges of ability, actual scores declined from age 2 to 19, likely due in part to limitations of appropriate tests. Use of Vineland-II daily living skills scores in place of NVIQ did not statistically improve the correspondence between age 2 and age 19 scores. Clinicians and researchers should use caution when making comparisons based on exact scores or specific ability ranges within or across individuals with ASD of different ages.
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Abbreviations
- ASD:
-
Autism spectrum disorders
- ID:
-
Intellectual disability
- NVIQ:
-
Nonverbal IQ
- DLS:
-
Daily living skills
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Acknowledgments
This work was supported by Grants from the National Institute of Mental Health (MH081873), the National Institute of Child Health and Human Development (U 19 HD 035482), and Autism Speaks (dated January 11, 2008) to Catherine Lord. The funding sources played no role in the writing of the manuscript or the decision to submit it for publication, including study design, recruitment of the sample, or the collection, analysis and interpretation of the data. The authors were not paid by a pharmaceutical company to write this article. The authors had full access to all of the data in the study as well as the final responsibility for the decision to submit for publication. The views expressed in this paper do not necessarily represent the views of the NIMH, NIH, HHS, or the United States Government. The authors are grateful to all of the participating families in this study, as well as Pamela DiLavore, Cory Shulman, and Susan Risi for their critical roles in data collection. We thank Shanping Qiu for technical assistance with the data. We also gratefully acknowledge Catherine Lord for her input on the manuscript.
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Bishop, S.L., Farmer, C. & Thurm, A. Measurement of Nonverbal IQ in Autism Spectrum Disorder: Scores in Young Adulthood Compared to Early Childhood. J Autism Dev Disord 45, 966–974 (2015). https://doi.org/10.1007/s10803-014-2250-3
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DOI: https://doi.org/10.1007/s10803-014-2250-3