The Mandarin Chinese version of the childhood autism spectrum test (CAST): test-retest reliability.

This study aimed to investigate the test-retest reliability of a Mandarin Chinese version of the Childhood Autism Spectrum Test (CAST), in a Chinese population. Parents in a school based study on the prevalence of ASC in mainland China were asked to complete a second version of the CAST approximately 2-4 months after first completion. Test retest data were available from 70 children (questionnaires completed by the same parent). Using a cut-off score of 15, the test-retest reliability was good (kappa=0.64). The test-retest reliability in three categories (≤ 11, 12-14, ≥ 15) was moderate (weighted kappa=0.53). The correlation between the scores at CAST-1 and CAST-2 was good (Spearman rho=0.73). The Mandarin CAST demonstrated moderate to good test-retest reliability as a screening instrument for ASC in an assessment sample in mainland China.