Economic Evaluation of the Thai Diagnostic Autism Scale for Autism Spectrum Disorder Diagnosis in Children Aged 1-5 Years Old

The Thai Diagnostic Autism Scale (TDAS) was developed for autism spectrum disorder (ASD) diagnosis in Thai children aged 1-5 years. Previous studies have indicated its good performance; however, additional health resources and healthcare providers are necessary for evaluation. Therefore, this study aimed to assess the cost-effectiveness of TDAS compared to clinical diagnosis (ClinDx) for ASD diagnosis in Thai children aged 1-5 years from a societal perspective. The analysis employed a hybrid model consisting of a decision tree model for a diagnostic phase with a state transition model for a follow-up phase. A literature review was conducted to determine TDAS performance and the relative risk of death in patients with ASD. Direct medical costs were assessed through a retrospective medical records review, and a cross-sectional survey was conducted to determine direct nonmedical costs, ASD severities, and utility values. The cost of TDAS was derived from a healthcare provider interview (n = 10). The incremental cost-effectiveness ratio (ICER) compared the total lifetime cost and quality-adjusted life years (QALY) between TDAS and ClinDx. We found that TDAS could improve QALY by 1.96 but increased total lifetime cost by 5577 USD, resulting in an ICER of 2852 USD/QALY. Sensitivity analysis indicated an 81.16% chance that TDAS is cost-effective. The probabilities of different ASD severities were key influencing factors of the findings. In conclusion, TDAS is the cost-effective option for ASD diagnosis in Thai children aged 1-5 years compared to ClinDx, despite some uncertainties around inputs. Further monitoring and evaluation are warranted if TDAS is to be implemented nationwide.

Factors Associated with Suspected Developmental Delay in Thai Children Born with Low Birth Weight or Asphyxia

OBJECTIVES

The aim of the study was to identify factors associated with a risk of suspected developmental delay (SDD) in high-risk children in Thailand.

METHODS

We used data on children enrolled for developmental delay (DD) screening across Thailand collected by the Rajanagarindra Institute of Child Development, Department of Mental Health, Ministry of Public Health, Thailand. Children who were under 5 years of age with a birth weight of fewer than 2500 g and/or birth asphyxia in Thailand with high risk of DD were assessed using the Developmental Assessment for Intervention Manual (DAIM) between August 2013 and November 2019 (N = 14,314).

RESULTS

The high-risk children who had a gestational age at birth of < 37 weeks (adjusted odds ratio = 1.54; 95% confidence interval = 1.39-1.70) and/or had a birth weight < 2500 g (1.22; 1.02-1.45), or had mothers who were not government officers (1.46; 1.11-1.93), had a low education level (1.36; 1.19-1.55), had a poor nutritional status (1.34; 1.09-1.65), and/or who were living in a high-altitude area (1.59; 1.32-1.91) were at a higher risk of SDD.

CONCLUSIONS FOR PRACTICE

Children with a low birth weight and/or asphyxia during birth had a high risk of DD. SDD monitoring of children by community health workers and/or by developing outreach strategies, especially in underserved regions, should be considered. In addition, developing policies and guidelines, and intervention for high-risk children ought to be conducted to reduce the subsequent problems caused by the late detection of DD.

A 9-year retrospective cohort study of the monitoring and screening of childhood developmental delay in Thailand

BACKGROUND

Developmental delay in early childhood can have negative long-term cognitive and psychiatric sequelae, along with poor academic achievement, so early screening and surveillance are paramount. The aim of this study is to evaluate the impact of screening and surveillance on child developmental delay using the Developmental Surveillance and Promotion Manual (DSPM) and the Thai Early Developmental Assessment for Intervention (TEDA4I) for Thai children aged 0-5 years old.

METHODS

Data were obtained from the routine developmental screening for specific disorders at ages 9, 18, 30, 42 and 60 months conducted using DSPM and TEDA4I from 2013 to 2021. Descriptive statistics were used to analyse the data, and the results are visualised graphically herein.

RESULTS

Only 56% of the children were screened for child developmental delay using DSPM. The proportion of children screened increased from <1% in 2013 to 90% in 2021. Suspected developmental delay prevalence increased significantly from 3.91% in 2013-2015 to 10.00% in 2016-2018 and 26.48% in 2019-2021. Moreover, of the children with suspected developmental delay who received developmental stimulation within a month, only 87.9% returned for follow-up visits when they were evaluated again using TEDA4I to ascertain any abnormalities and specific areas of deficit. The overall proportion of children diagnosed with developmental delay was 1.29%. During the pandemic, the proportion of screening tests for child developmental delay at routine vaccination visits and follow-ups decreased but was still at least 80% in each region.

CONCLUSIONS

Since 1%-3% of children have suspected developmental delay, early detection is key to treating it as soon as possible. We anticipate that our findings will raise awareness in parents and caregivers about childhood developmental delay and lead to the implementation of early intervention and follow-up at the rural level in Thailand.

Development and psychometric evaluation of a Thai Diagnostic Autism Scale for the early diagnosis of Autism Spectrum Disorder

The Thai Diagnostic Autism Scale (TDAS) was developed for use as a diagnostic tool for the early diagnosis of Autism Spectrum Disorder (ASD) in Thai children aged 12–48 months old. TDAS consists of 23 items (13 and 17 items in the observational and interview sections, respectively) classified into seven domains (A1–A3 and B1–B4) according to the criteria in the Diagnostic and Statistical Manual of Mental Disorder, fifth edition (DSM‐5). Children with a single score in the A1–A3 domains and at least two of the B1–B4 domains were classified with ASD. The item‐objective congruence (IOC) index, confirmatory factor analysis, and Kappa coefficient were used to evaluate the content, constructs, and inter‐rater validity levels between the evaluators and concurrent validity between TDAS and physicians' diagnoses, respectively. TDAS showed good overall content validity (IOC range 0.71–1.00), suitable construct validity (root‐mean‐squared errors of approximation of 0.076 and 0.067, comparative fit indexes of 0.902 and 0.858, and Tucker‐Lewis indexes of 0.882 and 0.837 for the observation and interview sections, respectively), and excellent diagnostic agreement between TDAS and the evaluators (Kappa = 1.000) as well as between TDAS and the physicians' diagnoses (Kappa = 0.871). The sensitivity and specificity of TDAS were 100% and 82.4%, respectively. In conclusion, TDAS yielded a high level of content validity, concurrent validity, and inter‐rater reliability for the early diagnosis of ASD in Thai children. A large‐scale study using TDAS is needed to determine an appropriate cut‐off point as well as its efficacy.

The Thai Diagnostic Autism Scale was developed for use as a diagnostic tool for the early diagnosis of Autism Spectrum Disorder (ASD) among Thai children. It contains 23 items in seven domains for the screening via observations and interviews. The psychometric properties of this diagnostic tool provide its reliability and suitability for the early diagnosis of ASD. A large‐scale study using it is needed to determine an appropriate cut‐off point as well as its efficacy.