Autism screening at 18 months of age: a comparison of the Q-CHAT-10 and M-CHAT screeners

Abstract

Background Autism screening is recommended at 18- and 24-month pediatric well visits. The Modified Checklist for Autism in Toddlers—Revised (M-CHAT-R) authors recommend a follow-up interview (M-CHAT-R/F) when positive. M-CHAT-R/F may be less accurate for 18-month-olds than 24-month-olds and accuracy for identification prior to two years is not known in samples that include children screening negative. Since autism symptoms may emerge gradually, ordinally scoring items based on the full range of response options, such as in the 10-item version of the Quantitative Checklist for Autism in Toddlers (Q-CHAT-10), might better capture autism signs than the dichotomous (i.e., yes/no) items in M-CHAT-R or the pass/fail scoring of Q-CHAT-10 items. The aims of this study were to determine and compare the accuracy of the M-CHAT-R/F and the Q-CHAT-10 and to describe the accuracy of the ordinally scored Q-CHAT-10 (Q-CHAT-10-O) for predicting autism in a sample of children who were screened at 18 months. Methods This is a community pediatrics validation study with screen positive (n = 167) and age- and practice-matched screen negative children (n = 241) recruited for diagnostic evaluations completed prior to 2 years old. Clinical diagnosis of autism was based on results of in-person diagnostic autism evaluations by research reliable testers blind to screening results and using the Autism Diagnostic Observation Schedule—Second Edition (ADOS-2) Toddler Module and Mullen Scales of Early Learning (MSEL) per standard guidelines. Results While the M-CHAT-R/F had higher specificity and PPV compared to M-CHAT-R, Q-CHAT-10-O showed higher sensitivity than M-CHAT-R/F and Q-CHAT-10. Limitations Many parents declined participation and the sample is over-represented by higher educated parents. Results cannot be extended to older ages. Conclusions Limitations of the currently recommended two-stage M-CHAT-R/F at the 18-month visit include low sensitivity with minimal balancing benefit of improved PPV from the follow-up interview. Ordinal, rather than dichotomous, scoring of autism screening items appears to be beneficial at this age. The Q-CHAT-10-O with ordinal scoring shows advantages to M-CHAT-R/F with half the number of items, no requirement for a follow-up interview, and improved sensitivity. Yet, Q-CHAT-10-O sensitivity is less than M-CHAT-R (without follow-up) and specificity is less than the two-stage procedure. Such limitations are consistent with recognition that screening needs to recur beyond this age.

Sensitivity and Specificity of the Modified Checklist for Autism in Toddlers (Original and Revised)

“…Most of the 51 studies (n = 40 [78%]) used concurrent detection methods, defined as evaluation to confirm ASD status within 6 months of screening. These studies included (1) additional rigorous false-negative case detection approaches, such as asking pediatric physicians to note ASD concerns, using additional screening tools for all or a subset of the sample (n = 21), or both; or (2) evaluation of all children regardless of screening results (n = 17) . In addition, 2 studies used strategies that were classified as weak concurrent false-negative case confirmation strategies, defined as strategies that resulted in few children who had not screened positive being invited for an evaluation .…”

“…Specificity similarly ranged from 0.27 to 1.00, with a pooled specificity of 0.94 (95% CI, 0.89-0.97). See Table 1 for screening metrics for each identified study, Table 2 for HSROC model results, and Figure 2 for a forest plot of included studies, sorted by sensitivity . The SROC plot of the overall model is depicted in eFigure 2 in Supplement 1.…”

Detección temprana de Trastorno del Espectro Autista: revisión de las herramientas de tamizaje validadas en Chile

“…En un estudio prospectivo, se concluyó que el Q-CHAT aplicado a los 18-30 tiene una sensibilidad del 44%, especificidad de un 98%, y valor predictivo positivo de 28%, para la identificación de niños que fueron diagnosticados con TEA a los 4 años 60 . Estudios que comparan los CHAT de autismo han demostrado valores variables de sensibilidad y especificidad 34,61 .…”

Aplicativo móvel para a triagem e gestão do Transtorno de Espectro Autista na Atenção Primária

“…O M-CHAT-R/F apresentou maior especificidade e valor preditivo positivo quando comparado com outros instrumentos de triagem para TEA aos 18 meses de idades (31). Analogamente, estudos (32) analisaram a relevância do M-CHAT-R por disponibilizar informações importantes para o diagnóstico do TEA e confirmaram que esta escala é o instrumento mais exato que permite triagem precoce e o acompanhamento dos sintomas do transtorno.…”