The Experts below are selected from a list of 24 Experts worldwide ranked by ideXlab platform
M Suzanne E Lewis - One of the best experts on this subject based on the ideXlab platform.
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trends in autism prevalence Diagnostic Substitution revisited
Journal of Autism and Developmental Disorders, 2008Co-Authors: Helen Coo, Helene Ouellettekuntz, Jennifer E V Lloyd, Liza Kasmara, Jeanette J A Holden, M Suzanne E LewisAbstract:There has been little evidence to support the hypothesis that Diagnostic Substitution may contribute to increases in the administrative prevalence of autism. We examined trends in assignment of special education codes to British Columbia (BC) school children who had an autism code in at least 1 year between 1996 and 2004, inclusive. The proportion of children with an autism code increased from 12.3/10,000 in 1996 to 43.1/10,000 in 2004; 51.9% of this increase was attributable to children switching from another special education classification to autism (16.0/10,000). Taking into account the reverse situation (children with an autism code switching to another special education category (5.9/10.000)), Diagnostic Substitution accounted for at least one-third of the increase in autism prevalence over the study period.
Craig J Newschaffer - One of the best experts on this subject based on the ideXlab platform.
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investigating Diagnostic Substitution and autism prevalence trends
Pediatrics, 2006Co-Authors: Craig J NewschafferAbstract:In this issue of Pediatrics , Dr Shattuck presents findings from his intensive statistical analysis of Diagnostic Substitution in US special education data.1 Diagnostic Substitution is one factor potentially contributing to the large observed increase in autism prevalence and, unlike many other possible factors, empirical evaluation of this factor can actually be approached by using existing administrative data. However, analyses of this sort are not without their challenges and complexities. When considering Diagnostic Substitution in US special education data, we are limited to group-level comparisons. We do not know whether individual children have switched classifications, and of course we can never know whether a given child in a particular birth cohort would have been classified differently had they been born either earlier or later. At best, analyses of this type are merely trying to determine if trends in one classification have the potential to offset those in another. Although Shattuck's models incorporate a number of advantageous features, they essentially distill the assessment of this … Address correspondence to Craig J. Newschaffer, PhD, Department of Epidemiology, Center for Autism and Developmental Disabilities Epidemiology, Johns Hopkins Bloomberg School of Public Health, 615 N Wolfe St, Room E6030, Baltimore, MD 21205. E-mail: cnewscha{at}jhsph.edu
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analysis of prevalence trends of autism spectrum disorder in minnesota
JAMA Pediatrics, 2003Co-Authors: James G Gurney, Craig J Newschaffer, Melissa S Fritz, Kirsten K Ness, Phillip Sievers, Elsa ShapiroAbstract:Background Alarming increases in the prevalence of autism spectrum disorder have been reported recently in the United States and Europe. Objectives To quantify and characterize prevalence trends over time in autism spectrum disorder in Minnesota. Methods We conducted an age-period-birth cohort analysis of special educational disability data from the Minnesota Department of Children, Families & Learning from the 1981-1982 through the 2001-2002 school years. Results Prevalence rates of autism spectrum disorder rose substantially over time within single-age groups and increased from year to year within birth cohorts. Autism spectrum disorder prevalence among children aged 6 to 11 years increased from 3 per 10 000 in 1991-1992 to 52 per 10 000 in 2001-2002. All other special educational disability categories also increased during this period, except for mild mental handicap, which decreased slightly from 24 per 10 000 to 23 per 10 000. We found that federal and state administrative changes favoring identification of autism spectrum disorders corresponded in time with the increasing rates. Conclusions We observed dramatic increases in the prevalence of autism spectrum disorder as a primary special educational disability starting in the 1991-1992 school year, and the trends show no sign of abatement. We found no corresponding decrease in any special educational disability category to suggest Diagnostic Substitution as an explanation for the autism trends in Minnesota. We could not assess changes in actual disease incidence with these data, but federal and state administrative changes in policy and law favoring better identification and reporting of autism are likely contributing factors to the prevalence increases and may imply that autism spectrum disorder has been underdiagnosed in the past.
Liza Kasmara - One of the best experts on this subject based on the ideXlab platform.
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trends in autism prevalence Diagnostic Substitution revisited
Journal of Autism and Developmental Disorders, 2008Co-Authors: Helen Coo, Helene Ouellettekuntz, Jennifer E V Lloyd, Liza Kasmara, Jeanette J A Holden, M Suzanne E LewisAbstract:There has been little evidence to support the hypothesis that Diagnostic Substitution may contribute to increases in the administrative prevalence of autism. We examined trends in assignment of special education codes to British Columbia (BC) school children who had an autism code in at least 1 year between 1996 and 2004, inclusive. The proportion of children with an autism code increased from 12.3/10,000 in 1996 to 43.1/10,000 in 2004; 51.9% of this increase was attributable to children switching from another special education classification to autism (16.0/10,000). Taking into account the reverse situation (children with an autism code switching to another special education category (5.9/10.000)), Diagnostic Substitution accounted for at least one-third of the increase in autism prevalence over the study period.
Paul T Shattuck - One of the best experts on this subject based on the ideXlab platform.
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Diagnostic Substitution and changing autism prevalence
Pediatrics, 2006Co-Authors: Paul T ShattuckAbstract:I am grateful to the editor of Pediatrics for selecting my article on Diagnostic Substitution in US special education for comment and doubly honored that Dr Newschaffer,1 an esteemed epidemiologist and autism researcher, rendered that commentary. Newschaffer explores some of the limitations of my analyses including reliance on aggregate-level associations to make the case for Diagnostic Substitution, the inability to disentangle cohort effects in these data, and an incomplete discussion of the magnitude of association between changes in autism prevalence and corresponding changes in the prevalence of other categories. I have acknowledged and explored most of these limitations in my discussion and will not reiterate those points here. However, there are 2 comments to which I would like to … Address correspondence to Paul T. Shattuck, PhD, 533B Waisman Center, University of Wisconsin, 1500 Highland Ave, Madison, WI 53705. E-mail: shattuck{at}waisman.wisc.edu
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the contribution of Diagnostic Substitution to the growing administrative prevalence of autism in us special education
Pediatrics, 2006Co-Authors: Paul T ShattuckAbstract:OBJECTIVE. Growing administrative prevalence of autism has stirred public controversy and concern. The extent to which increases in the administrative prevalence of autism have been associated with corresponding decreases in the use of other Diagnostic categories is unknown. The main objective of this study was to examine the relationship between the rising administrative prevalence of autism in US special education and changes in the use of other classification categories. METHODS. The main outcome measure was the administrative prevalence of autism among children ages 6 to 11 in US special education. Analysis involved estimating multilevel regression models of time-series data on the prevalence of disabilities among children in US special education from 1984 to 2003. RESULTS. The average administrative prevalence of autism among children increased from 0.6 to 3.1 per 1000 from 1994 to 2003. By 2003, only 17 states had a special education prevalence of autism that was within the range of recent epidemiological estimates. During the same period, the prevalence of mental retardation and learning disabilities declined by 2.8 and 8.3 per 1000, respectively. Higher autism prevalence was significantly associated with corresponding declines in the prevalence of mental retardation and learning disabilities. The declining prevalence of mental retardation and learning disabilities from 1994 to 2003 represented a significant downward deflection in their preexisting trajectories of prevalence from 1984 to 1993. California was one of a handful of states that did not clearly follow this pattern. CONCLUSIONS. Prevalence findings from special education data do not support the claim of an autism epidemic because the administrative prevalence figures for most states are well below epidemiological estimates. The growing administrative prevalence of autism from 1994 to 2003 was associated with corresponding declines in the usage of other Diagnostic categories.
Helen Coo - One of the best experts on this subject based on the ideXlab platform.
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trends in autism prevalence Diagnostic Substitution revisited
Journal of Autism and Developmental Disorders, 2008Co-Authors: Helen Coo, Helene Ouellettekuntz, Jennifer E V Lloyd, Liza Kasmara, Jeanette J A Holden, M Suzanne E LewisAbstract:There has been little evidence to support the hypothesis that Diagnostic Substitution may contribute to increases in the administrative prevalence of autism. We examined trends in assignment of special education codes to British Columbia (BC) school children who had an autism code in at least 1 year between 1996 and 2004, inclusive. The proportion of children with an autism code increased from 12.3/10,000 in 1996 to 43.1/10,000 in 2004; 51.9% of this increase was attributable to children switching from another special education classification to autism (16.0/10,000). Taking into account the reverse situation (children with an autism code switching to another special education category (5.9/10.000)), Diagnostic Substitution accounted for at least one-third of the increase in autism prevalence over the study period.