The Checklist for Autism Spectrum Disorder (CASD; Mayes, 2012) is a diagnostic and screening tool that consists of a comprehensive list of 30 ASD symptoms, scored as present (either currently, or in the past) or absent, based on a semi-structured interview with the parent; information from the child’s teacher or child care provider; observations of the child; and other available records. The CASD is unique because it was designed to assess autism as a spectrum, rather than using distinct subtypes, which is consistent with the DSM-5. The 30 items on the CASD were developed to describe the broad range of symptoms (organized into six categories) displayed by individuals with ASD in order to help parents and others to understand that relationship between these behaviors and ASD. Moreover, the CASD can be used to design a treatment program by targeting symptoms for intervention. It can be used for children with any level of intelligence. A sample video of the parent interview is included on the publisher’s website.
Age: 1 year to 17 years
Time to Administer: 15 minutes
Method of Administration: Thirty items scored by the clinician based on a semi-structured interview with the parent, information from the teacher or other care provider, observations of the child, and records. Symptoms are scored based on a lifetime occurrence.
Subscales: Overall Total Score, based on six domains
Problems with Social Interaction; Perseveration; Somatosensory Disturbance; Atypical Communication and Development; Mood Disturbance; Problems with Attention and Safety
Autism Related Research
Prior to its publication, the test author and colleagues published several studies about the developing measure. For example, Mayes and colleagues (2009) documented high interrater reliability (r = .72), found the CASD to differentiate those with ASD from those with ADHD with 99.5% accuracy, and determined diagnostic agreement with existing measures was high, including the CARS (98%) and GADS (94%). Later, Murray, Mayes, and Smith (2011) found high agreement (93.1%) between the CASD and the Autism Diagnostic Interview- Revised. Studies relevant to the use of the instrument after its publication are included in the table below.
Age Range: 3-17 years
Sample Size: 3,067
Validation of CASD-Short Form
A six-item subset of the CASD that discriminated best between children with ASD and ADHD with comorbid disorders. CASD-SF. Internal consistency was high for the six items (0.70-.87). The CASD-SF discriminated between with 100% accuracy using a cut-off score > 3 = ASD; it yielded a 98.5% diagnostic accuracy in the validation sample. Conclusion: the CASD-SF completed by the clinician using information from multiple sources has excellent diagnostic accuracy (>97%) and agreement with other autism measures (>95%), which supports its use as a component of a comprehensive autism diagnostic evaluation.
Tierney, Mayes, Lohs, Black, Gisin, & Veglia (2015)
Age Range: 24-55 months
Sample Size: 30
Diagnostic accuracy of CASD
Outcome:Tierney, Mayes, Lohs, Black, Gisin, & Veglia (2015)
CASD identified children with and without ASD with 96.7% accuracy, which is similar to the accuracy of 99.5% reported in the CASD manual for the standardization sample.
Conclusion: the CASD does not overemphasize autism in children without autism is a valid way for diagnosing autism in very young children with developmental delays, even when they also have apraxia.
Mayes, Black, & Tierney (2013)
Age Range: 1–16 years
Sample Size: 125
Diagnostic agreement between CASD, DSM-5, DSM-IV
Outcome:Mayes, Black, & Tierney (2013)
CASD agreement with DSM-IV was 91%. DSM-5 criteria (in this and other published studies) identifies fewer children with ASD than does the DSM-IV criteria. When one less symptom was required for a DSM-5 ASD diagnosis, diagnostic agreement between the DSM-5 and CASD increased from 82% to 93%.