TY  - JOUR
T1  - AUtism from 2 to 9 years of age
AU  - Lord C, Risi S, DiLavore PS, Shulman C, Thurm A, Pickles A
Y1  - 2006/06/01
N1  - 10.1001/archpsyc.63.6.694
JO  - Archives of General Psychiatry
SP  - 694
EP  - 701
VL  - 63
IS  - 6
N2  - Context 
    Autism represents an unusual pattern of development beginning in the infant and toddler years.Objectives 
    To examine the stability of autism spectrum diagnoses made at ages 2 through 9 years and identify features that predicted later diagnosis.Design 
    Prospective study of diagnostic classifications from standardized instruments including a parent interview (Autism Diagnostic Interview–Revised [ADI-R]), an observational scale (Pre-Linguistic Autism Diagnostic Observation Schedule/Autism Diagnostic Observation Schedule [ADOS]), and independent clinical diagnoses made at ages 2 and 9 years compared with a clinical research team's criterion standard diagnoses.Setting 
    Three inception cohorts: consecutive referrals for autism assessment to (1) state-funded community autism centers, (2) a private university autism clinic, and (3) case controls with developmental delay from community clinics.Participants 
    At 2 years of age, 192 autism referrals and 22 developmentally delayed case controls; 172 children seen at 9 years of age.Main Outcome Measures 
    Consensus best-estimate diagnoses at 9 years of age.Results 
    Percentage agreement between best-estimate diagnoses at 2 and 9 years of age was 67, with a weighted κ of 0.72. Diagnostic change was primarily accounted for by movement from pervasive developmental disorder not otherwise specified to autism. Each measure at age 2 years was strongly prognostic for autism at age 9 years, with odds ratios of 6.6 for parent interview, 6.8 for observation, and 12.8 for clinical judgment. Once verbal IQ (P = .001) was taken into account at age 2 years, the ADI-R repetitive domain (P = .02) and the ADOS social (P = .05) and repetitive domains (P = .005) significantly predicted autism at age 9 years.Conclusions 
    Diagnostic stability at age 9 years was very high for autism at age 2 years and less strong for pervasive developmental disorder not otherwise specified. Judgment of experienced clinicians, trained on standard instruments, consistently added to information available from parent interview and standardized observation.
SN  - 0003-990X
M3  - doi: 10.1001/archpsyc.63.6.694
UR  - http://dx.doi.org/10.1001/archpsyc.63.6.694
ER  -