Modified Checklist For Autism In Toddlers Research Articles

Estimación de la prevalencia de los trastornos del espectro autista en Canarias

AimsTo make an initial estimate of the prevalence of autism spectrum disorders (ASDs) among children in the province of Las Palmas (Spain). Material and methodsDescriptive study was conducted on 1,796 children between the ages of 18 and 30 months of age, all part of the Child Health Surveillance of the Canary Islands, more specifically the province of Las Palmas, with a population of 1,090,605. The parents of children involved completed the Spanish version of the Modified Checklist for Autism in Toddlers (M-CHAT/ES) in the paediatric clinic. The positive cases were then diagnosed by experts by means of the Autism Diagnostic Interview-Revised (ADIR) and the Autism Diagnostic Observation Schedule (ADOS). ResultsA 0.61% prevalence of ASDs was determined, similar to that reported in previous studies using the same tools. The ratio was six girls for every five boys. This was contrary to the results of previous studies which suggested more boys than girls were affected. This may have been due to the sample size, which will have to be increased in future studies to confirm this outcome. ConclusionsAn increased sample size and also spread to other age ranges should be used in order to obtain a more reliable estimate of prevalence. As regards the gender ratio, this could be a result of the small size of the sample researched, and should therefore be confirmed by further studies.

Large-Scale Use of the Modified Checklist for Autism in Low-Risk Toddlers

The purpose of the study was to examine use of the Modified Checklist for Autism in Toddlers (M-CHAT) as an autism-specific screening instrument in a large, geographically diverse pediatrics-based sample. The M-CHAT and the M-CHAT Follow-Up (M-CHAT/F) were used to screen 18,989 toddlers at pediatric well-child visits in 2 US geographic regions. Pediatricians directly referred children to ascertain potential missed screening cases. Screen-positive children received the M-CHAT/F; children who continued to screen positive after the M-CHAT/F received a diagnostic evaluation. Results indicated that 54% of children who screened positive on the M-CHAT and M-CHAT/F presented with an autism spectrum disorder (ASD), and 98% presented with clinically significant developmental concerns warranting intervention. An M-CHAT total score cutoff of ≥3 identifies nearly all screen-positive cases, and for ease of scoring the use of only the M-CHAT total score cutoff is recommended. An M-CHAT total score of 7 serves as an appropriate clinical cutoff, and providers can bypass the M-CHAT/F and refer immediately to evaluation and intervention if a child obtains a score of ≥7. This study provides empirical support for the utility of population screening for ASD with the use of the M-CHAT in a primary care setting. Results suggest that the M-CHAT continues to be an effective screening instrument for ASD when the 2-step screening process is used. The M-CHAT is widely used at pediatric offices, and this study provides updated results to facilitate use and scoring of the M-CHAT by clinical providers.

Screening accuracy for risk of autism spectrum disorder using the Brief Infant-Toddler Social and Emotional Assessment (BITSEA)

Early identification of autism spectrum disorders (ASDs) is facilitated by the use of standardized screening scales that assess the social emotional behaviors associated with ASD. Authors examined accuracy of Brief Infant-Toddler Social and Emotional Assessment (BITSEA) subscales in detecting Modified Checklist for Autism in Toddlers (M-CHAT) risk for 456 toddlers. An ASD-specific screener, Total ASD, was developed from BITSEA subscales incorporating both behavioral and social communicative features of ASD. Results indicated that Total ASD is more accurate in detecting autism risk than scales measuring general behavior problems or social competence. Results provide support for the BITSEA as a Level I screener for social emotional problems and a Level II screener for ASD symptoms at community sites such as well child clinics.

The Modified Checklist for Autism in Toddlers: Reliability in a Diverse Rural American Sample

This study investigated the psychometric properties of the modified checklist for autism in toddlers (M-CHAT) in a diverse rural American low-socioeconomic status (SES) sample. Four hundred and forty-seven English (n=335) and Spanish (n=112) speaking caregivers completed the M-CHAT during their toddler's 18- or 24-month well visit in a Southwest Virginia pediatric clinic. The M-CHAT did not show acceptable internal consistency in groups with low maternal education or minority status. Caregivers reporting low maternal education and minority status were more likely to endorse items suggestive of autism. These results indicate that the M-CHAT may require modifications to be more internally consistent and accurate across ethnic and educational groups in rural areas with low levels of SES. Recommendations to increase the utility of the M-CHAT are discussed.

Screening for autism in low-birth-weight Egyptian toddlers

EnAbstract Background In recent times major advances have been made in the field of early detection of autism in infants, and validated screening tools now exist to facilitate the early and accurate screening of infants before further referral for specialized autism diagnostic testing. Objective The aim of this study was to screen low-birth-weight (LBW) toddlers for early autistic features compared with normal controls and identify the associated risk factors. Materials and methods This cross-sectional study included 100 toddlers (24–30 months old) with a history of LBW. They were screened for autism using the Modified Checklist for Autism in Toddlers (M-CHAT). Further assessment was made using the Childhood Autism Rating Scale (CARS), Vineland Social Maturity Scale, and Arabic Language Test. One hundred age-matched and sex-matched full-term toddlers with a history of average birth weight and uneventful natal, perinatal, and postnatal history were included as the control group. Results The toddlers with LBW had a significantly higher frequency of positive M-CHAT screening than did the controls (11% of LBW children vs. 2% of controls). Positively screened LBW toddlers had significantly higher parental age at conception, lower birth weight, higher frequency of small-for-gestational-age preterms as well as higher incidence of gestational bleeding when compared with negatively screened LBW. They also had lower language and social ages than the negatively screened LBW. M-CHAT scores of positively screened LBW children correlated positively with maternal age at conception and negatively with birth weight, social age, and language age. Five of the 11 positively screened LBW children and one of the two positively screened controls were confirmed to have autism on the basis of CARS. Conclusion LBW is probably an independent risk factor associated with the development of autism. Early screening for autism is recommended for the LBW population especially if associated with risk factor(s) or if showing early impairment of social and language abilities, to be followed by definitive autism testing in those with positive screening results.

Effectiveness of Developmental Screening in an Urban Setting

To determine the effectiveness of developmental screening on the identification of developmental delays, early intervention (EI) referrals, and EI eligibility. This randomized controlled, parallel-group trial was conducted from December 2008 to June 2010 in 4 urban pediatric practices. Children were eligible if they were <30 months old, term, without congenital malformations or genetic syndromes, not in foster care, and not enrolled in EI. Children were randomized to receive 1 of the following: (1) developmental screening using Ages and Stages Questionnaire-II (ASQ-II and Modified Checklist for Autism in Toddlers (M-CHAT) with office staff assistance, (2) developmental screening using ASQ-II and M-CHAT without office staff assistance, or (3) developmental surveillance using age-appropriate milestones at well visits. Outcomes were assessed using an intention-to-treat analysis. A total of 2103 children were enrolled. Most were African-American with family incomes less than $30,000. Children in either screening arm were more likely to be identified with delays (23.0% and 26.8% vs 13.0%; P < .001), referred to EI (19.9% and 17.5% vs 10.2%; P < .001), and eligible for EI services (7.0% and 5.3% vs 3.0%; P < .001) than children in the surveillance arm. Children in the screening arms incurred a shorter time to identification, EI referral, and EI evaluation than children in the surveillance arm. Children who participated in a developmental screening program were more likely to be identified with developmental delays, referred to EI, and eligible for EI services in a timelier fashion than children who received surveillance alone. These results support policies endorsing developmental screening.

Developmental and Autism Screening Through 2-1-1: Reaching Underserved Families

Developmental disorders, including autism spectrum disorders (ASDs), are increasing in prevalence. Early identification is necessary for early intervention, which is critical for reducing challenges and lifetime costs, especially for ASDs. Because not all children have equal access to developmental and autism screening through primary care settings, nontraditional methods are needed to reach underserved populations. In this proof-of-concept study, the 2-1-1 Los Angeles County Developmental Screening Project (2-1-1 LA Project) provided developmental and autism screening by telephone in a population of low-income and racially and ethnically diverse children. Aggregate data were reviewed for 2845 children who were screened for developmental delays using the Parents' Evaluation of Developmental Status (PEDS) instrument and/or autism using the Modified Checklist for Autism in Toddlers (M-CHAT) instrument between September 1, 2009, and October 31, 2011. Data analysis was conducted December 2011 through February 2012. A majority of children (56%) screened with the PEDS had a moderate to high risk of developmental delays, including 28.2% classified as high-risk, which indicates need for further evaluation. Among 1605 children screened with the M-CHAT, 21.2% had an elevated risk of ASDs. Follow-up care coordination was provided for 2625 children to facilitate completion of referrals for diagnostic evaluation, early childhood education, and other developmental or behavioral needs. The project's approach enhanced access to screenings and referral uptake in a population of children that may have difficulty accessing primary care. Findings suggest the potential of nontraditional developmental screening models.

Screening Children for Autism in an Urban Clinic Using an Electronic M-CHAT

The Modified Checklist for Autism in Toddlers (M-CHAT) is a screening tool for autism spectrum disorders in the clinic. However, the follow-up questions in the M-CHAT are difficult to implement on a paper format. To compare the effectiveness of the M-CHAT on an electronic format versus paper format in an outpatient clinic setting. Methods. A prospective study used electronic M-CHAT on the iPad. A retrospective review of paper M-CHATs 6 months prior to implementation was used as the comparison group. A total of 176 participants completed the electronic M-CHAT format and 197 paper M-CHATs were retrospectively reviewed. The electronic format (3%) resulted in a significant difference in the frequency of children found to be at risk for autism compared with the paper version (11%); 99% of parents rated the experience as "good" or "excellent." The electronic format lowered both false at-risk screens and false not-at-risk screens and had higher parental satisfaction.

Early identification of autism: A comparison of the Checklist for Autism in Toddlers and the Modified Checklist for Autism in Toddlers

There is still debate as to what is the most effective strategy for identifying the early signs of autism in very young children. Two levels of screening having been advocated: broad-based developmental surveillance and targeted screening. Two popular tools for use in developmental surveillance are the Checklist for Autism in Toddlers (CHAT) and the Modified Checklist for Autism in Toddlers (M-CHAT). The purpose of this article is to summarise the current evidence for screening for autistic symptoms in very young children using CHAT and M-CHAT. A systematic search was carried out of electronic database and other sources for original studies which evaluated the use of CHAT and M-CHAT in screening for autism in children younger than 5 years of age. Studies were included for review if they evaluated the sensitivity and/or specificity of CHAT or M-CHAT, or described the best age to administer these instruments. The available evidence suggests that characteristic behaviours in autism should be evident in simple forms before the age of 18 months, while screening at 24 months should be conducted to identify those who regress. Administering a screening tool during 18- to 24-month well-child visits improves early identification of autism, while the stability of diagnosis at the ages of 18 months and 24 months is confirmed. M-CHAT has slightly better sensitivity and specificity compared to CHAT, and is preferable to use as a developmental surveillance screening instrument.

True versus false positives and negatives on the Modified Checklist For Autism in Toddlers

Given the importance of early intervention services for children with autism spectrum disorders (ASD), early diagnosis of children is critical. At present, several ASD screeners exist for young children, with the Modified Checklist for Autism in Toddlers (M-CHAT) being one of the most widely researched. While the M-CHAT has good sensitivity and specificity, the presence of false positives and false negatives is inevitable. While false positives are not as disconcerting, since follow-up assessment will reveal the absence of ASD, false negatives can inadvertently delay much needed services to toddlers. The current study examined parental report for 552 toddlers who were referred for early intervention services due to being part of an at-risk population. The groups were divided into four groups based on their M-CHAT scores and actual diagnoses – a true positive group (n=150), false positive group (n=150), true negative group (n=151), and false negative group (n=101). All four groups were compared with respect to their total M-CHAT score and total critical items score on the M-CHAT. While the true positive and false positive groups significantly differed from the true negative and false negative groups on both of these dimensions, significant differences were also found between the true and false positive groups but not between the true and false negative groups. Furthermore, all 23 M-CHAT items were more commonly endorsed by individuals in the true positive group when compared to the false positive group, while differences in item endorsements between the true and false negative groups were scant. Based on these results, the true and false positive groups tended to be more easily discriminated from one another while the true and false negative groups presented themselves similarly. The implications of these findings are discussed.

An Abbreviated Screening Instrument for Autism Spectrum Disorders

AbstractThe reliability and validity of the Parent's Observations of Social Interactions (POSI), a new, seven‐item screening instrument for autism spectrum disorders (ASD), is examined in two substudies. In Study 1, parents of 217 children (18–48 months) evaluated at a developmental clinic completed intake questionnaires that included the POSI and the Modified Checklist for Autism in Toddlers (M‐CHAT) checklist. POSI and M‐CHAT scores were compared to clinical evaluation results to assess reliability and validity. In Study 2, parents of 232 children (16–36 months) from both primary care and subspecialty settings completed the POSI, the M‐CHAT, and a report of their child's diagnoses. POSI and M‐CHAT scores were compared to reported diagnoses to assess reliability and validity. In both studies, the POSI demonstrated adequate internal reliability (Cronbach α = 0.83 and 0.86, respectively). In Study 1, POSI sensitivity (89%) was higher than that for the M‐CHAT (71%; p &lt; .05); specificities were not significantly different (POSI: 54%, M‐CHAT: 62%). In Study 2, sensitivity (83%) compared favorably to that for the M‐CHAT (50%), although specificity was lower (75 vs. 84%). Despite its brevity, the POSI demonstrated good internal reliability and comparable sensitivity/specificity to the M‐CHAT checklist in two independent populations. If results are reproduced in larger, more diverse samples, the POSI may provide an efficient method for ASD screening in young children.

M-CHAT Mexican Version Validity and Reliability and Some Cultural Considerations.

The Modified Checklist for Autism in Toddlers (M-CHAT) questionnaire is a brief measure available in Spanish which needs to be validated for the Mexican population. Parents of children from (1) community with typical development (TD) and (2) psychiatric outpatient unit completed the CBCL/1.5–5 and the Mexican/MM-CHAT-version. The study sample consisted of 456 children (age M = 4.46, SD = 1.12), 74.34% TD children and 26.65% with Autism Spectrum Disorders (ASD). The MM-CHAT mean score for failed key items was higher for the ASD group compared with the TD group. Internal consistency for the Mexican/M-CHAT version was .76 for total score and .70 for the 6 critical items. Correlations between the MM-CHAT and the CBCL/1.5: PDD and Withdrawn subscales and with ADI-R dimensions: B non verbal) and A were high, and were moderate with ADI-R dimensions B1 (verbal) and C The failure rate of the MM-CHAT between the groups did not reproduce all the critical items found in other studies. Although the instrument has good psychometric properties and can be used for screening purposes in primary settings or busy specialized psychiatric clinics, these results support evidence for cultural differences in item responses, making it difficult to compare M-CHAT results internationally.

Screening for autism in extremely preterm infants: problems in interpretation

The aim of this article was to report the prevalence of, and risk factors for, positive autism screens using the Modified Checklist for Autism in Toddlers (M-CHAT) in children born extremely preterm in England. All children born at not more than 26 weeks' gestational age in England during 2006 were recruited to the EPICure-2 study. At 2 years of age, postal questionnaires incorporating the M-CHAT and additional developmental questions were sent to the parents of each survivor (n=1031; 499 male, 532 female), of which 523 (266 male, 257 female; 51%) were returned completed. The prevalence of positive M-CHAT screens in this extremely preterm population was 41% (216/523; 130 male; 86 female). Severe bronchopulmonary dysplasia, administration of postnatal steroids, late-onset bacteraemia, and being male were statistically significantly associated with a positive screen. Coexisting disabilities were present in 320 (62%) children. Of 200 children without disability, 16.5% screened positive. In contrast, 63 (95.5%) of those with severe motor impairment (odds ratio 42; 95% confidence interval [CI] 12.9-135) and 175 (55.9%) of those with cognitive impairment (odds ratio 5.3; CI 3.5-8) screened positive. All children with a significant vision or hearing impairment screened positive. The prevalence of positive M-CHAT screens in extremely preterm children is high, especially in children with neurodevelopmental impairment. Positive screens should be interpreted in the light of other neurodevelopmental sequelae in clinical practice to avoid false-positive referrals.

Indicadores clínicos precoces de los trastornos generalizados del desarrollo

IntroductionPervasive development disorders (PDD) conditions characterised by deficits in many areas of behaviour, such as delay in social interactions, abnormalities in verbal and non-verbal communication, and the presence of the restrictive and repetitive interests. The relevance of early diagnosis is based on the fact that early intervention could have a beneficial effect on the long term outcome. Due to the increase of the PDD diagnosis in the recent years, we aimed to study easily detectable clinical traits during the first year of life, leading to an improvement in the diagnosis. Patients and interventionsA prospective and retrospective study was conducted on 37 PDD patients and 69 healthy controls. Somatometric and neurological examinations were performed and a questionnaire with several variables from the Modified Checklist for Autism in Toddlers (M-CHAT) completed by the parents. ResultsThe male to female ratio (OR: 3.87; 95% CI: 1.23-12.96), delay in the first disyllabic words (PDD=20.1±23 months vs Control=10.8±10.3 months; P<.01), absence of visual contact (OR: 0.05; 95% CI: 0.01-0.29), the lack of response to attention call (OR: 0.12; 95% CI: 0.02-0.67), and the increase in tantrums (OR: 6.37; 95% CI: 2.39-17.34), were significantly higher in the PDD group. ConclusionsThe differences detected between groups can not been considered as a diagnostic tool of certainty in this time period, however, we believe that they should be considered in the context of maturational delay, as alarm signs in infants and toddlers, as well as suggesting the existence of an early pervasive development phenotype.

Atypical social development in neonatal intensive care unit survivors at 12 months

Owing to advances in neonatal intensive care, many infants who are hospitalized in neonatal intensive care units (NICU) can survive and grow, and are referred to as NICU survivors. However, social development in NICU survivors has not been fully explored. To examine the social development of NICU survivors, a questionnaire consisting of the Modified Checklist for Autism in Toddlers (M-CHAT) was used. The M-CHAT was completed by the parents of either NICU survivors (n= 117) or normally delivered children (control group, n= 112) during their regular medical checkups at a corrected age of 12 months. Ninety percent of NICU survivors and 63% of control children did not pass the M-CHAT screen. As it was originally designed for children aged 18-30 months, failed M-CHAT items could have been due to developmental issues and not due to autistic spectrum disorders. However, there was a significant difference in the total number of items failed between the two groups. In particular, many NICU survivors did not pass on M-CHAT items, such as oversensitivity to noise, unusual finger movements, and attempts to attract attention. Concerning perinatal complications, infants with low birthweight and/or the need for respiratory support tended to have a higher number of failures on all M-CHAT items. NICU survivors may have distinct developmental patterns of social communication, and should be followed up for assessment of social skills and neurological development.

Defining characteristics for young children meeting cutoff on the modified checklist for autism in toddlers

Early diagnosis of Autism Spectrum Disorders (ASDs) is crucial so that early intervention services, which have been found to best alleviate symptoms of ASD in children, can be implemented. Currently, the Modified Checklist for Autism in Toddlers ( M-CHAT) and the Baby and Infant Screen for Children with aUtIsm Traits-Part 1 ( BISCUIT-Part 1) are the most widely researched ASD measures in early childhood. However, the M-CHAT provides many false positive results as it is solely used as a screening instrument as opposed to a diagnostic measure, while the BISCUIT-Part 1 appears to have more diagnostic fidelity. The current study examined 243 toddlers who failed the M-CHAT screener and were therefore referred for further evaluation. Upon further evaluation, 141 of the toddlers were diagnosed with an ASD while the remaining 102 were not. Characteristics differentiating these two groups on the M-CHAT, BISCUIT-Part 1, and Battelle Developmental Inventory, Second Edition ( BDI-II) were examined with analyses supporting the hypotheses that children in the ASD group had higher M-CHAT and BISCUIT-Part 1 scores in conjunction with lower BDI-II scores. Based on these results, the incremental predictive validity of the M-CHAT was assessed; the BISCUIT-Part 1 was found to be more accurate in arriving at ASD diagnoses. The implications of these findings are discussed.

Autism Screening Strikes Emotional Chord

AFTER AN ARTICLE THAT DISCOURagesroutineautismscreeningappearedonline inPediatrics, coauthor JanWillemGorter,MD,PhD,heard an array of heartfelt responses. “Some peoplewereupset,especiallyparentswith a child with autism,” said Gorter, an associate professor of pediatrics in the McMaster University Faculty of Health Sciences in Hamilton, Ontario, Canada. “I also got responses of parents who had a child mislabeled with autism initially, and that had a huge impact on the parents’ life and the child’s life.” The study struck an emotional chord by concluding that sound evidence to support routine screening is lacking (AlQabandi M et al. Pediatrics. 2011;128[1]: e211-e217). The authors say that currently available autism screening tools have not been evaluated in randomized controlled trials and that treatment is only modestly effective in certain subgroups of children. Although childhood screening, early detection, and treatmentareeffective for conditions such as congenital hypothyroidism or phenylketonuria, Gorter and his colleagues say that existing evidence doesnot showthat routine screening for autismdoesmoregoodthanharm.Infact, theysaythatmisdiagnosescanstigmatize children, expose them to unnecessary treatment, and trigger excessive costs. Gorter noted that the article focuses on routine screening that includes apparently healthy children, not clinical surveillance in which pediatricians evaluate children because they or the parents suspect a problem. The data were taken from a literature search designed to answer 7 questions concerning the appropriateness, feasibility, and value of screening for autism. In 2007, the American Academy of Pediatrics (AAP) published a clinical report that supports screening all children, regardless of risk factors, for autism spectrum disorders beginning at age 18 months (Johnson CP et al. Pediatrics. 2007;120[5]:1183-1215). For children without risk factors, the AAP report says appropriate evaluation methods include several screening tools that consist of parental interviews, questionnaires, or direct observation of the child. Among them are the Checklist for Autism in Toddlers (CHAT) and the Modified Checklist for Autism in Toddlers (M-CHAT). Both are available at no cost to primary care pediatricians. The reported specificity of CHAT is at least 98%, but sensitivity is between 18% and 38%. M-CHAT has 93% specificity and 85% sensitivity. Gorter and his colleagues say that M-CHAT, a 23item questionnaire that takes parents about 5 minutes to complete, is a “promising” tool, but that it misses 15 of every 100 children with autism. They say that none of the currently available screening tests “fulfill the properties of accuracy, namely high sensitivity, high specificity, and high predictive value” in population-based screening programs. Gorter said he and his colleagues did not intend for their study to split clinicians into “right” and “wrong” camps. “We took a scientific approach,” he said. “We wanted to consider not only what we know about testing itself, but also the impact of the screening program on public health and society at large.” Catherine Lord, PhD, director of the UniversityofMichiganAutismandCommunication Disorders Center in Ann Arbor, said the study lacks a necessary ingredient: a thoroughcost-benefit analysis. “We need to know what is the cost of screening and the benefit of screening, and what is the cost of treatment and the benefit of treatment,” said Lord, who was not involved in Gorter’s research. “It’s certainly not true that we can cure autism, but to say that nobody has ever shown a treatment has any effectiveness, any generalizability, that’s just not true.” Fred R. Volkmar, MD, director of the Child Study Center at the Yale University School of Medicine, agreed that interventions for autism do make a differ-

Modified Checklist for Autism in Toddlers (M-CHAT) screening at 18 months of age predicts concurrent understanding of desires, word learning and expressive vocabulary

The Modified Checklist for Autism in Toddlers (M-CHAT) is a 23-item questionnaire used in primary screening of Autism Spectrum Disorder (ASD). The current studies examine the concurrent validity of the M-CHAT in its ability to predict 18-month-olds’ performance on theory of mind and word learning tasks. In Experiment 1, infants’ understanding of desires was tested using a modified food request task. Experiment 2 assessed infants’ ability to learn novel words. Results indicate that infants’ score on the M-CHAT significantly predicts their performance on both the desire understanding and the novel word learning task. As expected, the number of items endorsed on the M-CHAT also relates to infants’ expressive vocabulary at 18 months of age. Taken together, these findings confirm the concurrent validity of the M-CHAT at the youngest age this measure can reliably be administered. Within a broader clinical context, the present results provide preliminary evidence that controlled laboratory tasks assessing early social cognitive and verbal abilities could be added to the battery of screening instruments for ASD.

The Modified Checklist for Autism in Toddlers in extremely low gestational age newborns: individual items associated with motor, cognitive, vision and hearing limitations

The Modified Checklist for Autism in Toddlers (M-CHAT) has yielded elevated rates of screening failure for children born preterm or with low birthweight. We extended these findings with a detailed examination of M-CHAT items in a large sample of children born at extremely low gestational age. The sample was grouped according to children's current limitations and degree of impairment. The aim was to better understand how disabilities might influence M-CHAT scores. Fourteen participating institutions of the Extremely Low Gestational Age Newborns (ELGAN) Study prospectively collected information about 1086 infants who were born before the 28th week of gestation and had an assessment at age 24-months. The 24-month visit included a neurological assessment, the Bayley Scales of Infant Development, Second edition (BSID-II), M-CHAT and a medical history form. Outcome measures included the distribution of failed M-CHAT items among groups classified according to cerebral palsy diagnosis, gross motor function, BSID-II scores and vision or hearing impairments. M-CHAT items were failed more frequently by children with concurrently identified impairments (motor, cognitive, vision and hearing). In addition, the frequency of item failure increased with the severity of impairment. The failed M-CHAT items were often, but not consistently, related to children's specific impairments. Importantly, four of the six M-CHAT 'critical items' were commonly affected by presence and severity of concurrent impairments. The strong association between impaired sensory or motor function and M-CHAT results among extremely low gestational age children suggests that such impairments might give rise to false positive M-CHAT screening.

Examination of the Properties of the Modified Checklist for Autism in Toddlers (M-CHAT) in a Population Sample

This study examines the following properties of the Modified Checklist for Autism in Toddlers (M-CHAT) in an unselected low-risk sample: (a) the maximum age for screen administration; (b) the positive screen rate in the absence of follow-up telephone interviews and; (c) the distributional properties of positive screens. Data came from a prospective cohort study (n=1,604). Results suggest that the M-CHAT can appropriately be administered to children aged 20-48months. Documented explanations provided by mothers during screening, appear to effectively identify potential screen misclassifications in the absence of the follow-up telephone interviews. This further emphasizes the importance of clinician expertise in verifying positive M-CHAT screens. Results have implications for the administration of the M-CHAT in clinical and research settings.