Sensitivity and Specificity of Proposed DSM-5 Diagnostic Criteria for Autism Spectrum Disorder - Validation

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Sensitivity and Specificity of Proposed DSM-5 Diagnostic Criteria for

Autism Spectrum Disorder. <http://www.ncbi.nlm.nih.gov/pubmed/22449643>

McPartland JC, Reichow B, Volkmar FR.

J Am Acad Child Adolesc Psychiatry. 2012 Apr;51(4):368-83.

OBJECTIVE: This study evaluated the potential impact of proposed DSM-5

diagnostic criteria for autism spectrum disorder (ASD).

METHOD:

The study focused on a sample of 933 participants evaluated during the

DSM-IV field trial; 657 carried a clinical diagnosis of an ASD, and 276

were diagnosed with a non-autistic disorder. Sensitivity and specificity

for proposed DSM-5 diagnostic criteria were evaluated using field trial

symptom checklists as follows: individual field trial checklist items

(e.g., nonverbal communication); checklist items grouped together as

described by a single DSM-5 symptom (e.g., nonverbal and verbal

communication); individual DSM-5 criterion (e.g., social-communicative

impairment); and overall diagnostic criteria.

RESULTS: When applying proposed DSM-5 diagnostic criteria for ASD, 60.6%

(95% confidence interval: 57%-64%) of cases with a clinical diagnosis of

an ASD met revised DSM-5 diagnostic criteria for ASD. Overall

specificity was high, with 94.9% (95% confidence interval: 92%-97%) of

individuals accurately excluded from the spectrum. Sensitivity varied by

diagnostic subgroup (autistic disorder = 0.76; Asperger's disorder =

0.25; pervasive developmental disorder-not otherwise specified = 0.28)

and cognitive ability (IQ < 70 = 0.70; IQ ? 70 = 0.46).

CONCLUSIONS: Proposed DSM-5 criteria could substantially alter the

composition of the autism spectrum. Revised criteria improve specificity

but exclude a substantial portion of cognitively able individuals and

those with ASDs other than autistic disorder. A more stringent

diagnostic rubric holds significant public health ramifications

regarding service eligibility and compatibility of historical and future

research.

Validation of proposed DSM-5 criteria for autism spectrum disorder.

<http://www.ncbi.nlm.nih.gov/pubmed/22176937>

Frazier TW, Youngstrom EA, Speer L, Embacher R, Law P, Constantino J,

Findling RL, Hardan AY, Eng C.

J Am Acad Child Adolesc Psychiatry. 2012 Jan;51(1):28-40.e3.

OBJECTIVE: The primary aim of the present study was to evaluate the

validity of proposed DSM-5 criteria for autism spectrum disorder (ASD).

METHOD: We analyzed symptoms from 14,744 siblings (8,911 ASD and 5,863

non-ASD) included in a national registry, the Interactive Autism

Network. Youth 2 through 18 years of age were included if at least one

child in the family was diagnosed with ASD. Caregivers reported symptoms

using the Social Responsiveness Scale and the Social Communication

Questionnaire. The structure of autism symptoms was examined using

latent variable models that included categories, dimensions, or hybrid

models specifying categories and subdimensions. Diagnostic efficiency

statistics evaluated the proposed DSM-5 algorithm in identifying ASD.

RESULTS: A hybrid model that included both a category (ASD versus

non-ASD) and two symptom dimensions (social communication/interaction

and restricted/repetitive behaviors) was more parsimonious than all

other models and replicated across measures and subsamples. Empirical

classifications from this hybrid model closely mirrored clinical ASD

diagnoses (90% overlap), implying a broad ASD category distinct from

non-ASD. DSM-5 criteria had superior specificity relative to DSM-IV-TR

criteria (0.97 versus 0.86); however sensitivity was lower (0.81 versus

0.95). Relaxing DSM-5 criteria by requiring one less symptom criterion

increased sensitivity (0.93 versus 0.81), with minimal reduction in

specificity (0.95 versus 0.97).

CONCLUSIONS: Results supported the validity of proposed DSM-5 criteria

for ASD as provided in Phase I Field Trials criteria. Increased

specificity of DSM-5 relative to DSM-IV-TR may reduce false positive

diagnoses, a particularly relevant consideration for low base rate

clinical settings. Phase II testing of DSM-5 should consider a relaxed

algorithm, without which as many as 12% of ASD-affected individuals,

particularly females, will be missed. Relaxed DSM-5 criteria may improve

identification of ASD, decreasing societal costs through appropriate

early diagnosis and maximizing intervention resources.

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