We investigated if shifts in the coding of qualifying conditions in the California Department of Developmental Services (DDS) have contributed to the increase in California children with autism observed in recent years. Qualifying condition codes for mental retardation (MR) and autism in DDS electronic files were compared to hard-copy records for samples of children born 1987, 1990, 1994, and 1997. Contrary to expectations, we did not find evidence of a coding shift from “MR only” to “both MR and autism” or an increase in the proportion of children with coded autism who lacked supportive diagnostic documentation in records (possible “misclassifications”). These results indicate that changes in DDS coding practices are unlikely to explain the increase in DDS clients with autism.
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We wish to express appreciation to DDS for providing us with data sets for these analyses, for assisting us with understanding the complexities of this administrative database, and for reviewing the manuscript for accuracy in description of DDS data. We also wish to thank the Regional Centers for their cooperation with our field data collection. Any errors in calculation or interpretation of data are those of the authors, not DDS or Regional Centers. We are grateful to Meredith Anderson, MA, for her statistical and programming contribution, to Daniel Smith, DrPH for statistical consultation, and to our talented field data collection staff who carefully reviewed records and abstracted data for this analysis. Funding was provided in part by the California Department of Public Health and in part by a cooperative agreement with the Centers for Disease Control and Prevention, National Center for Birth Defects and Developmental Disabilities (CDC U10/CCU920392).
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Grether, J.K., Rosen, N.J., Smith, K.S. et al. Investigation of Shifts in Autism Reporting in the California Department of Developmental Services. J Autism Dev Disord 39, 1412–1419 (2009). https://doi.org/10.1007/s10803-009-0754-z
- Autism reporting
- California DDS autism