title: Evaluation of regression in autism spectrum disorder based on parental reports.
abstract: BACKGROUND
  Research indicates that some children with autism spectrum disorder (ASD) experience a developmental regression.
  
  
  OBJECTIVE
  The study examined the percentage of children with autism, pervasive developmental disorder (PDD), ASD, and Asperger syndrome (AS) who were considered to be delayed (D), regressed (R), or delayed and later regressed (DR) and examined any relationship with autism severity, time of onset, factors associated with onset, gastrointestinal (GI) symptoms, race, age, and gender.
  
  
  METHODS
  The study reviewed developmental and medical information based on parental reports of 135 children with a diagnosis of autism, PDD, ASD, or AS.
  
  
  RESULTS
  The number of children in the D group was 53 (39.2%) with 19 (14.1%) in the DR group and 63 (46.7%) in the R group. Thus, 82 children (60.7%) were reported to have R. In regard to onset of symptoms, there was a significant difference between the D and R groups as well as between the DR and R groups. The analyses showed that there was no significant relationship between age, gender, race, severity, or GI symptoms and membership in any group; D, DR, or R. The majority of parents reported that the regression was preceded by or was associated with vaccinations (57.3%) or another medically related event (11.0%).
  
  
  CONCLUSIONS
  The findings are consistent with previous research and reinforce our understanding of regression in those children with an ASD diagnosis.
authors.affiliation: Department of Research, Institute of Chronic Illness, Inc., Silver Spring, Maryland ; Department of Psychiatry, University of Texas Southwestern Medical Center, Dallas, Texas, USA.
authors.forename: Janet K
authors.initials: JK
authors.lastname: Kern
authors.affiliation: Department of Research, Institute of Chronic Illness, Inc., Silver Spring, Maryland.
authors.forename: David A
authors.initials: DA
authors.lastname: Geier
authors.affiliation: Department of Research, Institute of Chronic Illness, Inc., Silver Spring, Maryland.
authors.forename: Mark R
authors.initials: MR
authors.lastname: Geier
keywords: Autism spectrum disorder; asperger syndrome; childhood autism rating scale; delay; development; parental report; pervasive developmental disorder not otherwise specified; regression