The Use of M-CHAT (Malay version) As a Screening Tool for Pervasive Developmental Disorders in Malaysia

Background:

The Modified Checklist for Autism in Toddlers (M-CHAT, 1999) was translated in 2008 to Malay, the Malaysian national language (M-CHAT-Malay Version; MCHAT-MV). MCHAT-MV has been used nationwide in maternal and child health clinics in Malaysia from 2012 until the present time. Typically MCHAT-MV would be given to parents by community nurses if there were developmental or behavioural concerns. The results would guide nurses regarding referrals to tertiary diagnostic autism services or to the clinic medical officer. A small initial validation study of MCHAT-MV was performed but there were no subsequent studies. There are no Pervasive Developmental Disorders (PDD) screening tools used for children above 30 months in public health services.

Objectives:

The objective of this study was to determine the sensitivity and specificity of the MCHAT-MV as a screening tool for PDDs in children aged 18 to 60 months with developmental or behavioural problems. Optimal cut-off scores were also evaluated.

Methods:

A prospective study was done in the Child Developmental Centre (CDC) of a tertiary hospital from 1^st April 2010 until 31^stMay 2012. Parents of children aged 18 – 60 months referred as new cases for developmental or behavioural difficulties, were given the MCHAT-MV to fill in before clinical assessments. The diagnosis of PDD was made after 2 clinic appointments, including a developmental assessment, multi-disciplinary discussion and semi-structured interview and clinical observation by experienced developmental pediatricians using criteria from the Diagnostic and Statistical Manual of Mental Disorders 4th Edition, Text Revision (DSM IV-TR). Diagnosis of other developmental- behavioral disorders were made by developmental pediatricians.

Results:

A total of 130 patients were enrolled and categorized into two main groups, the PDD group and Other Developmental-Behavioural Disorder (ODB) group. The PDD patients were diagnosed with Autistic Disorder (n=50) and Pervasive Developmental Disorder – Not Otherwise Specified (PDD-NOS) (n=13). The ODB patients were diagnosed with Global Developmental Delay (n=20), Specific Language Impairment (n=41) and Attention Deficit Hyperactive Disorder (n=6). The MCHAT-MV was found to have the sensitivities and specificities respectively for the corresponding age-groups: overall 18-60 months (n=130), 88.9% and 47.8%; 25-30 months (n=38), 100% and 45.5%; aged 37 – 48 months (n=59), 90.3% and 57.1% and 49 – 60 months (n=27), 80.0% and 50%. Children aged 18-24 months were not analysed in a stratified age group there was only 1 child with autistic disorder. Overall positive predictive value (PPV) was 61.5% while negative predictive value (NPV) was 82.0%. Optimal cut-off values to detect PDD based on the Receiver Operator Characteristic (ROC) curve were failing 1 out of the 6 critical items or 3 of 23 total items from the MCHAT-MV.

Conclusions:

MCHAT-MV is a sensitive screening tool for detecting Malaysian children with PDDs in an expanded age group of 25 – 48 months old in this selected population. The original cut off value of 3 of 23 total items can be used in our population, however further studies are needed to determine the cut-off value for critical items. All children failing MCHAT-MV will require further evaluation due to moderate specificity.