The study evaluated the stability over time of the Q-CHAT (i.e., Quantitative-CHecklist for Autism in Toddler), a screening tool for the early detection of Autism. The Q-CHAT is filled by parents when the child is from 18-36 months old, and whether a risk score is found, the clinician refers the child to a more in-depth diagnostic evaluation. Previous studies demonstrated the measure test-retest reliability on a small time interval (1-6 months). Therefore, the present study tested the stability of the scores considering a larger time interval of 18 months. No previous studies have tested its measurement invariance over time. Since the tool is filled by parents during a large time span (18-36 months of life), it is imperative to understand whether there is an invariance over time in their evaluations. The Italian version of the Q-CHAT was completed by 282 parents of children with no pre-existing signs of risk of Autism. The Q-CHAT was administered when children were 18 months (T1) and then 18 months later (T2). The intraclass correlation coefficients for the test-retest reliability ranged from sufficient to moderate. The measurement invariance across time revealed a tolerable configural and metric invariance. Contrary, the scalar invariance was not met meaning that the means of the constructs are not invariant over time. The findings give a further demonstration of the reliability of the Q-CHAT. They give evidence that changes in the scores would reflect real changes in the construct itself, and not in the way individuals interpret the measure items.
Test-retest Reliability and Measurement Invariance across time of the Quantitative-CHecklist for Autism in Toddler
LEVANTE, ANNALISA
;PETROCCHI, SERENA;LECCISO, Flavia
2021-01-01
Abstract
The study evaluated the stability over time of the Q-CHAT (i.e., Quantitative-CHecklist for Autism in Toddler), a screening tool for the early detection of Autism. The Q-CHAT is filled by parents when the child is from 18-36 months old, and whether a risk score is found, the clinician refers the child to a more in-depth diagnostic evaluation. Previous studies demonstrated the measure test-retest reliability on a small time interval (1-6 months). Therefore, the present study tested the stability of the scores considering a larger time interval of 18 months. No previous studies have tested its measurement invariance over time. Since the tool is filled by parents during a large time span (18-36 months of life), it is imperative to understand whether there is an invariance over time in their evaluations. The Italian version of the Q-CHAT was completed by 282 parents of children with no pre-existing signs of risk of Autism. The Q-CHAT was administered when children were 18 months (T1) and then 18 months later (T2). The intraclass correlation coefficients for the test-retest reliability ranged from sufficient to moderate. The measurement invariance across time revealed a tolerable configural and metric invariance. Contrary, the scalar invariance was not met meaning that the means of the constructs are not invariant over time. The findings give a further demonstration of the reliability of the Q-CHAT. They give evidence that changes in the scores would reflect real changes in the construct itself, and not in the way individuals interpret the measure items.I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.
