Heterogeneity of Language Development in Young Children with Autism Over 4-5 Years Karen D. Bopp, Ph.D., S-LP(C) Pat Mirenda, Ph.D., BCBA The University of British Columbia, Canada November 20, 2008 American Speech and Hearing Association Convention Chicago, USA OVERVIEW Language development and autism BC longitudinal study of early intervention outcomes Study 1: Changes in development over time Study 2: Behaviour predictors of language development over 2 years Study 3: Prelinguistic predictors of language development over 4 to 5 years Summary and future Directions Language Development and Autism Performance-based theory language disorders are secondary to limitations in individual child factors cognitive processing (e.g., motivation, attention, memory, and retention) social-affective skills (e.g., imitation, joint attention, reciprocity, etc.) Social-interactionist perspective language is developed through a motivation to interact socially with others; social experiences, in turn, motivate the acquisition of many dimensions of language (2008) 1
Variability in Outcomes It is estimated that only approximately 15% of individuals with autism are reasonably selfsufficient as adults and another 15% to 20% function well with periodic support Majority of Research in Early Intervention Outcomes Continuum of Approaches in Communication Enhancement for Children with Autism Behavioural Social Pragmatic Developmental Prizant and Wetherby, 1998 Variability in Outcomes Lovaas (1987) 47% of children achieved normal intellectual and educational functioning, 40% had moderate cognitive challenges and were assigned to special classes, and 10% had severe cognitive challenges and were assigned to segregated settings at follow-up Sallows & Graupner (2005) 48% of children achieved IQ scores in the normal range and were placed in regular, age-level classrooms, while the remaining children made less dramatic progress Strain, Kohler, & Goldstien (1996) 47% of children in the LEAP preschool using incidental and naturalistic teaching techniques were placed in regular public school settings (2008) 2
The lack of 100% effectiveness of early intervention leads one to conclude that this is a heterogeneous population and that there are other variables affecting outcomes that have not yet been identified BC Longitudinal Study of Early Intervention Outcomes Contracted by the Ministry of Children and Family Development (MCFD) to conduct an evaluation of the early interventions for children with autism spectrum disorders 3 year term (2001-2004) Extended 2 years for follow-up (2005-2007) Data Collection collected at entry to EI; 6, 12, 24, 33, and 53 months later Participants N = 69 M age at T1 50 mo (4;2) M age at final data point (T6) (N = 41) 113 mo (9;4) Gender (males) at T1 83% M CARS score at T1 Autism/PDD-NOS 36.4 (25-50.5) Autism (n = 55) PDD-NOS (n = 14) M NVIQ (Mullen, WPPSI) at T1 48 (38-124) M Parent education at T1 2.6 (0.5-5.0) 2 = professional diploma 3 = some university/college English primary language at T1 80% (2008) 3
Early Intervention Received All of the children received approximately 15 to 20 hours per week of year-round early intervention services for 2 years EI Providers: Services provided through one of 3 EIBI programs or through individualized funding (IF) in BC Intervention for all children was eclectic and consisted of 1:1 instruction based on the principles of applied behavior analysis (ABA) as well as services from speech-language pathologists, occupational therapists, and other professionals (e.g., behavioral consultants) No significant differences were found between EIBI clinic-based programs and IF programs on any relevant measures Background: Overview of the Evaluation Measures Language and vocabulary comprehension and production (PLS-3; EOWPVT; PPVT- III; MCDI W&G or W&S) Adaptive behaviour (VABS) Cognitive development (Mullen, WPPSI, WISC) Autism severity (ABC and CARS) Parenting stress (PSI) Data collected from parent report (family interviews via questionnaires), S-LPs, and psychologists Study 1: Changes in language development over time (2008) 4
Question Does the trajectory of language development change during intervention versus after early intervention and upon school entry? Data Analysis Data files were constructed for all children who had at least one data point before and after EI funding expired at age 6 Resulting in n = 53 T-tests indicated that data were missing at random for all relevant measures, so n = 53 represents the total sample N = 69 Data Analysis SAS Proc Mixed analysis used to examine unconditional and conditional models for each outcome measure CA was used as a measure of time Conditional model examined nonverbal IQ (NVIQ), Childhood Autism Rating Scale (CARS) scores, and EI providers as predictors of intercept and slope Neither EI provider type nor CARS explained any variation in intercept or slope, either during or after EI NVIQ predicted variation in the slope of PPVT and VABS communication during EI but not after (2008) 5
Typical Development For the purpose of comparison, developmental trajectories were estimated for typical children, using information from the test manuals Raw scores were estimated at anchor points of M 50 mo (EI entry), 75 mo (post-ei data collection), and 113 months (final data collection) Typical rates of change were also estimated, using these time intervals EOWPVT Vocabulary Production Raw score 100 90 80 70 60 50 40 30 20 10 0 typical ASD.71.92.58.89 1.02 2;0.30 6 12 18 24 30 36 42 48 54 60 66 72 78 84 90 96 102 108 114 120 Child's Age in Months Vocabulary Comprehension PPVT (n = 49) (Four participants with NVIQ 85-124 were responsible for the NVIQ interaction; they were excluded from this analysis) 140 typical ASD 120 Raw score 100 80 60 40 20 0 1.03 1.3 1.01.73 1.16 2;6.29 6 12 18 24 30 36 42 48 54 60 66 72 78 84 90 96 102 108 114 120 Child's Age in Months (2008) 6
VABS Communication Raw score 120 100 80 60 40 20 typical ASD NVIQ >/= 50 ASD NVIQ </= 48.63.34.92 1.4.34 1.3.95 1.08.71 0 6 12 18 24 30 36 42 48 54 60 66 72 78 84 90 96 102 108 114 120 Child's Age in Months Summary During EI, mean rates of change increased compared to pre-ei rates Following EI, mean rates of change decreased (except for PPVT) Data also indicated significant heterogeneity in development Next step was to explore potential influences of development beyond NVIQ, autism severity, and age Move from examining how children perform at each stage of development to examining the processes by which children develop language This type of exploratory research can provide stronger predictions about how clinicians might intervene Study 2: Exploring behaviour predictors of language development over 2 years (2008) 7
What Do We Mean by Predictor? If a predictor occurs or is present at Time A, it is very likely that something else will occur or be present at Time B For example, if Harry eats or drinks a lot of sugar between ages 1-4 (Time A), it s very likely that he will have many dental cavities at ages 5-10 (Time B) So, we can say that high sugar eating or drinking behavior at Time A predicts high dental cavities at Time B Behaviour Predictors of Language Development Over 2 Years Purpose: To determine the influence of six clusters of child behaviours on changes in child development for young children with autism using a longitudinal design over 2 years Child Behaviours = Predictor Variables Acting-out behaviours Eating disturbances Stereotypic repetitive sensory motor behaviours Stereotypic insistence on sameness behaviours Social unresponsiveness Inattentiveness Question Does one or more types of child behaviour at T1 (baseline - prior to the start of intervention) predict changes in child language over 2 years (T1 to T4)? (2008) 8
Method of Analysis: Individual Growth Curve Modeling SAS Proc Mixed was used to explore what predicted the rate of change (ROC) in child language development over 2 years (i.e., individual growth trajectories) Results Social Unresponsiveness (SU) Included rarely smiling; not looking at faces; actively avoiding eye contact; and failing to respond to one s own name Regardless of T1 nonverbal IQ and autism severity, children with high scores for social unresponsiveness at T1 made significantly less progress in vocabulary comprehension; vocabulary production; and language comprehension over 2 years Results Inattentiveness (IA) Included not paying attention to sights and sounds in the environment; being distracted by noise; not listening to instructions or a story; and looking away from tasks to notice other actions in the room Regardless of T1 nonverbal IQ and autism severity, children with high scores for inattentive behaviors at T1 made significantly less progress in vocabulary production; and language comprehension over 2 years (2008) 9
Effect of T1 IA and SU scores on EOWPVT over 2 years Effect of T1 IA and SU scores on PLS AC over 2 years Effect of T1 SU scores on PPVT over 2 years (2008) 10
Summary Prior to the start of treatment, it appeared that inattentiveness and social unresponsiveness hindered language development Identifying predictive relationships can provide guidance for developing treatments that will result in better outcomes for young children with autism and their families Summary supports the common practice of providing focused instruction on attending skills early in the treatment process supports the notion that social-affective skills play a central role in language development in this population emphasizes the importance of early social behaviors on later language development. We still have much to learn about how addressing these predictors will impact outcomes for children with autism Study 3: Exploring prelinguistic predictors of language development over 4 to 5 years (2008) 11
Goal of the Study To identify early prelinguistic behaviors of young children with ASD that predict general language development 4-5 years later Participants 44 children with ASD 37 boys, 7 girls Average age before starting early intervention was 3 years 11 months (from 1 yr 8 months to 5 yrs 11 months) All children received early intervention services in British Columbia for 15-20 hrs/wk for an average of 2 years Assessments Each child all participated in assessments several times over 4-5 years: Before they started intervention (Time 1, T1) 6 months after T1 (T2) 12 months after T1 (T3) 24 months after T1 (T4) 30 months after T1 (T5) 55 months after T1 (T6) (2008) 12
Predictors?? The parents of all children completed a form called the MacArthur-Bates Communicative Development Inventory at T1 This provided information about the child s ability to: Predictors?? 1. Respond when his/her name is called 2. Respond to no 3. React to There s Mommy/Daddy by looking at them 4. Imitate sounds and words 5. Point to objects and name them 6. Point to objects to share them with others 7. Use other types of gestures such as waving bye-bye Predictors?? 8. Play games and routines such as peek-a-boo, so big, singing, and dancing 9. Pretend in functional ways, such as pretending to drink with a cup 10. Pretend to be a parent, such as feeding a doll with a bottle 11. Imitate other adult actions, such as pretending to vacuum 12. Understand phrases (2 words or more) (2008) 13
Data Analysis Examined Time 1 pre-language skills as predictors of development over 4 5 years PPVT (vocabulary comprehension) EOWPVT (vocabulary production) PLSAC (language comprehension) PLSEC (language production) VABS communication skills Method of Analysis Multi-level individual growth curve modeling using SAS Proc Mixed Analysis First, we looked at whether the children s autism severity and/or cognitive ability were predictors of language development Autism severity did not predict change over time. T1 NVIQ did predict the rate of change over 4-5 years Next, we looked at the 12 abilities on the MacArthur form to see if any of them were good predictors Two Predictors! Out of the 12 abilities we looked at, only two consistently predicted language development 4-5 years later: Ability to play games and routines Play peek-a-boo Play patty cake Play so big Play chase games Sing Dance Ability to point to objects and label them to another person (i.e., social labeling) (2008) 14
More Analysis Ward s Cluster analysis of T1 G&R and social labeling Divided the 44 children into those with Low games & routines and social labeling scores a T1 Medium games & routines and social labeling scores at T1 High games & routines and social labeling scores at T1 Also split each cluster into two groups Those with a HIGH T1 NVIQ 50; and Those with a LOW T1 NVIQ 48 PPVT RAW SCORE Vocabulary Comprehension: Rate of Change in PPVT over 4-5 years 80 70 60 50 40 30 20 10 0 6 12 18 24 30 36 42 48 54 60 66 72 78 84 90 96 102 108 114 120 Child's Age in Months Cluster A: G&R = 0/1 & Low Cluster A with Cluster B with Cluster C with 12% Labeling n=8 NVIQ 48 Cluster B: G&R = 2/3 & 12% labeling n=16 High NVIQ Cluster A with Cluster B with Cluster C with Cluster C: G&R = 4/5 & 50 35% labeling n=20 EOWPVT RAW SCORE Vocabulary Production: Rate of Change in EOWPVT over 4-5 years 80 70 60 50 40 30 20 10 0 Low NVIQ 48 High NVIQ 50 6 12 18 24 30 36 42 48 54 60 66 72 78 84 90 96 102 108 114 120 Cluster A with Cluster A with Child's Age in Months Cluster B with Cluster B with Cluster C with Cluster C with Cluster A: G&R = 0/1 & 12% Labeling n=8 Cluster B: G&R = 2/3 & 12% labeling n=16 Cluster C: G&R = 4/5 & 35% labeling n=20 (2008) 15
Language Comprehension: Rate of Change in PLS AC over 4-5 years 60 50 PLS AC RAW SCORE 40 30 20 10 0 6 12 18 24 30 36 42 48 54 60 66 72 78 84 90 96 102 108 114 120 Child's Age in Months Low NVIQ 48 High NVIQ 50 Cluster A with Cluster A with Cluster B with Cluster B with Cluster C with Cluster C with Cluster A: G&R = 0/1 & 12% Labeling n=8 Cluster B: G&R = 2/3 & 12% labeling n=16 Cluster C: G&R = 4/5 & 35% labeling n=20 Language Production: Rate of Change in PLS EC over 4-5 years 60 50 PLS EC RAW SCORE 40 30 20 10 0 6 12 18 24 30 36 42 48 54 60 66 72 78 84 90 96 102 108 114 120 Child's Age in Months Low NVIQ 48 High NVIQ 50 Cluster A with Cluster A with Cluster B with Cluster B with Cluster C with Cluster C with Cluster A: G&R = 0/1 & 12% Labeling n=8 Cluster B: G&R = 2/3 & 12% labeling n=16 Cluster C: G&R = 4/5 & 35% labeling n=20 Communication Skills: Rate of Change in VABS Com over 4.-5 years VABS Com RAW SCORE 100 90 80 70 60 50 40 30 20 10 0 6 12 18 24 30 36 42 48 54 60 66 72 78 84 90 96 102 108 114 120 Child's Age in Months Low NVIQ 48 High NVIQ 50 Cluster A with Cluster A with Cluster B with Cluster B with Cluster C with Cluster C with Cluster A: G&R = 0/1 & 12% Labeling n=8 Cluster B: G&R = 2/3 & 12% labeling n=16 Cluster C: G&R = 4/5 & 35% labeling n=20 (2008) 16
Summary Overall, regardless of T1 NVIQ, the T1 pre-language clusters significantly predicted the rate of change over time for all measures Rates of change for children in Cluster A (i.e., low G&R scores and 12% labeling) ranged from.09-.34 per month Rates of change for children in Cluster C (i.e., high G&R scores and 35% labeling) ranged from.40-.92 per month. Summary Children s ability, before the start of intervention to engage in simple games and other play routines and to point to objects and socially label them both appear to be related to how much progress they will make in language development over 4-5 years So What Does This Mean? Should parents and professionals be concerned if a young child cannot play games and routines such as peek-a-boo and patty cake, and cannot point and label objects? Yes and no! Yes, because if they don t have these skills, they may make less language progress over 4-5 years No, because even the children with low scores made progress (2008) 17
So What Does This Mean? If young children do not have these skills, how do we teach them? Think about what is required in order to do these skills: Turn taking Imitating actions and words Pointing, to label and to share information All of these skills occur during social play - - not play with toys, but social play -- so lots of social play is probably important! What Do Games and Routines Require? A number of skills that we know are good predictors of outcomes in and of themselves Immediate imitation skills Joint attention skills -- both initiating and responding Desire for social engagement Reciprocal social interaction skills So, the results suggest that EI should include specific focus on developing these skills, if they are not already present THANK-YOU FREE WebCasts http://setbc.org/setbc/topics/autism_dev_dis.html (2008) 18