Early Intervention for Toddlers With Language Delays: A Randomized Controlled Trial

Abstract

Early interventions for toddlers with expressive and receptive language delays have not resulted in positive expressive language outcomes. This randomized controlled trial tested the effects on language outcomes of a caregiver-implemented communication intervention targeting toddlers at risk for persistent language delays.
Participants included 97 toddlers, who were between 24 and 42 months with language scores at least 1.33 SDs below the normative mean and no other developmental delays, and their caregivers. Toddlers were randomly assigned to the caregiver-implemented intervention or a usual-care control group. Caregivers and children participated in 28 sessions in which caregivers were taught to implement the intervention. The primary outcome was the Preschool Language Scale, Fourth Edition, a broad-based measure of language. Outcome measurement was not blinded.
Caregivers in the intervention improved their use of all language facilitation strategies, such as matched turns (adjusted mean difference, intervention-control, 40; 95% confidence interval 34 to 46; P < .01). Children in the intervention group had significantly better receptive language skills (5.3; 95% confidence interval 0.15 to 10.4), but not broad-based expressive language skills (0.37, 95% confidence interval -4.5 to 5.3; P = .88).
This trial provides preliminary evidence of the short-term effects of systematic caregiver instruction on caregiver use of language facilitation strategies and subsequent changes in children's language skills. Future research should investigate the ideal dosage levels for optimizing child outcomes and determine which language facilitation strategies are associated with specific child outcomes. Research on adaptations for families from culturally and linguistically diverse backgrounds is needed.
Copyright © 2015 by the American Academy of Pediatrics.

Full text

Early Intervention for Toddlers With
Language Delays: A Randomized
Controlled Trial
Megan Y. Roberts, PhD, CCC-SLPa, Ann P. Kaiser, PhDb
abstract OBJECTIVE: Early interventions for toddlers with expressive and receptive language delays have
not resulted in positive expressive language outcomes. This randomized controlled trial tested
the effects on language outcomes of a caregiver-implemented communication intervention
targeting toddlers at risk for persistent language delays.
METHODS: Participants included 97 toddlers, who were between 24 and 42 months with language
scores at least 1.33 SDs below the normative mean and no other developmental delays, and their
caregivers. Toddlers were randomly assigned to the caregiver-implemented intervention or
a usual-care control group. Caregivers and childrenparticipatedin28sessionsinwhichcaregivers
were taught to implement the intervention. The primary outcome was the Preschool Language
Scale, Fourth Edition, a broad-based measure of language. Outcome measurement was not blinded.
RESULTS: Caregivers in the intervention improved their use of all language facilitation strategies,
such as matched turns (adjusted mean difference, intervention-control, 40; 95% confidence
interval 34 to 46; P,.01). Children in the intervention group had significantly better
receptive language skills (5.3; 95% confidence interval 0.15 to 10.4), but not broad-based
expressive language skills (0.37, 95% confidence interval 24.5 to 5.3; P= .88).
CONCLUSIONS: This trial provides preliminary evidence of the short-term effects of systematic
caregiver instruction on caregiver use of language facilitation strategies and subsequent
changes in children’s language skills. Future research should investigate the ideal dosage
levels for optimizing child outcomes and determine which language facilitation strategies are
associated with specific child outcomes. Research on adaptations for families from culturally
and linguistically diverse backgrounds is needed.
WHAT’S KNOWN ON THIS SUBJECT: Early
language delay is common in toddlers and is
associated with poor academic outcomes,
reading difficulties, and persistent
communication problems. Despite these long-
term sequelae, few interventions for toddlers
with early language delays yield positive
expressive and receptive language results.
WHAT THIS STUDY ADDS: A28-sessionprogram
delivered over 3 months can enhance parent
language facilitation strategies. Unusually, the
small short-term benefits were mainly in receptive,
rather than expressive, language and vocabulary.
Extended follow-up could determine the costs
versus benefits of this promising approach.
aRoxelyn and Richard Pepper Department of Communication Sciences and Disorders, School of Communication,
Northwestern University, Evanston, Illinois; and bDepartment of Special Education, Peabody College, Vanderbilt
University, Nashville, Tennessee
Dr Roberts coordinated and supervised the data collection, carried out the analyses, and drafted
the initial manuscript; Dr Kaiser reviewed and revised the manuscript; and both authors
conceptualized and designed the study and approved the final manuscript as submitted.
This trial has been registered at www.clinicaltrials.gov (identifier NCT01975922) and What Works
Clearinghouse (identifier R324A090181).
www.pediatrics.org/cgi/doi/10.1542/peds.2014-2134
DOI: 10.1542/peds.2014-2134
Accepted for publication Jan 22, 2015
Address correspondence to Megan Y. Rober ts, PhD, CCC-SLP/L, The Roxelyn and Richard Pepper
Department of Communication Sciences and Disorders, School of Communication, Northwestern
University, 2240 Campus Dr, Evanston, IL 60208. E-mail: megan.y.roberts@northwestern.edu
PEDIATRICS (ISSN Numbers: Print, 0031-4005; Online, 1098-4275).
Copyright © 2015 by the American Academy of Pediatrics
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Early language delay is common in
toddlers and is associated with
reading difficulties,
1
persisting
communication problems,
2
and poor
school readiness.
3
Approximately
15% of 24-month-old children have
language delays that are not due to
any identifiable etiology.
4
Although
the majority of toddlers with
expressive language delays are likely
to recover without intervention
(60%), toddlers with receptive and
expressive delays are substantially
less likely to recover spontaneously
(25%).
5
Despite this increased risk,
toddlers whose developmental delay
is restricted to language and who are
between 25% and 50% delayed in
that domain are not eligible to receive
early intervention services in half of
US states.
5
Only 3 intervention studies
examining children with receptive
and expressive language delays have
been published.
6–8
In the largest
randomized controlled trial of
a therapist-implemented intervention
for toddlers with language delays,
modest effects were found for
receptive language, and no effects
were found for expressive language.
6
However, the large range in intensity,
frequency, duration, and type of
therapy provided in the community-
based intervention limited the
interpretation of the results.
Caregiver-implemented interventions
for children with expressive and
receptive language delays have not
resulted in positive effects for
receptive and expressive language
skills.
7,8
The lack of effects in child
outcomes may be attributed to failure
to achieve differences in caregiver use
of language facilitation strategies
between intervention and control
groups
7
or the absence of systematic
caregiver instructional procedures
and measures of intervention
fidelity.
8
Given limitations in extant research,
the purpose of this study was to test
whether a 3-month caregiver-
implemented intervention targeting
toddlers at risk for persistent
language delays improved language
outcomes immediately after the end
of intervention. Identified evidence
gaps were addressed by targeting
toddlers with receptive and
expressive language delays, including
systematic caregiver instructional
procedures and measuring
caregivers’use of language facilitation
strategies continuously during
intervention to ensure that caregivers
were at high levels of fidelity.
We hypothesized that toddlers in the
intervention group, relative to
toddlers in the control group, would
have higher scores on (1)
standardized measures of expressive
and receptive language (primary
outcome), (2) standardized caregiver-
report and observational measures of
expressive vocabulary (secondary
outcome), and (3) standardized
measures of receptive vocabulary
(secondary outcome) immediately
after the end of the 3-month
intervention. We also hypothesized
that caregivers in the intervention
group would use more language
facilitation strategies than caregivers
in the control group (primary
outcome) and that the stress level of
caregivers in the intervention group
would not be greater than caregivers
in the control group (secondary
outcome) immediately after the end
of the 3-month intervention.
METHODS
Trial Design
The Working on Rapid Language
Development project was
a randomized controlled trial
(NCT01975922). The study was
conducted in Nashville, Tennessee.
The trial was approved by Vanderbilt
University’s Institutional Review
Board (090904), and all caregivers
provided written informed consent.
Participants
Toddlers and their caregivers were
recruited through the Tennessee
Early Intervention System, local
pediatricians’offices, and
advertisements placed in the local
Nashville Parent. Recruitment
occurred continuously from October
2009 to October 2013. Toddlers were
eligible for the trial if they were
between 24 and 42 months of age and
their expressive and/or receptive
language scores were at least 1.33 SD
below the normative mean of 10 on
the Bayley Scales of Infant and
Toddler Development, Third Edition
9
(scaled score #6). This score
corresponds to an expressive
vocabulary of ,8 words for a
24-month-old. Exclusion criteria
included intellectual disability,
hearing loss .40 dB, a major medical
condition, or a diagnosis of autism
spectrum disorder. Caregivers were
informed immediately after the
eligibility assessment if their children
met the inclusion criteria.
Randomization
Eligible toddlers were randomly
assigned to intervention or usual-care
control arms with a 1:1 ratio by using
a computer-generated random
number sequence. The randomization
sequence was concealed from the
study coordinator, who enrolled
participants and assigned
participants to study arms. Random
assignment occurred immediately
after the eligibility assessment.
Intervention
Once randomly assigned, participants
could not be naïve to the trial arm.
Caregivers in the control group did
not receive the intervention.
Information about the type and
amount of community-based
language intervention was collected
for all participants and is provided in
Table 1. All children in both trial arms
who had not previously been
evaluated were referred to the
Tennessee Early Intervention System
to determine their eligibility for
community-based services. The
intervention (Enhanced Milieu
Teaching
10
) was designed to promote
early language acquisition in
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everyday interactions. The
intervention included 2 components:
caregiver instruction and child
intervention. First, the caregiver
received individual instruction by
using the teach-model-coach-review
method (described below) to learn
how to use specific language
facilitation strategies at home with
their toddlers. Second, the caregiver
used 6 language facilitation strategies
during intervention sessions and
throughout the day with their child.
A summary of these intervention
components is provided in Fig 1.
A complete description of the
intervention is available in the
manualized intervention protocol.
11
Caregivers received 28 individual
instructional sessions (4 workshops,
24 practice sessions). One clinic
session and 1 home session occurred
weekly for 3 months. Missed sessions
were rescheduled. The format of each
session was standardized and
included (1) review of the strategy
taught in the workshop, (2) modeling
of the strategy by the interventionist
with the child, (3) caregiver practice
of the strategy with their child while
the interventionist provided coaching,
and (4) review of the session.
Modeling and practice occurred in
play interactions and routines such as
reading a book or eating a meal.
A video example of practice with
coaching is provided in Fig 2. Sessions
lasted ∼1 hour.
Because early language delay is highly
variable at young ages and caregivers
vary in their use of language
facilitation strategies, the intervention
was individualized in 2 ways. First,
specific language targets were chosen
for each child based on performance
during the baseline assessments. All
toddlers had either (1) single word
targets if they used ,50 total words
and 10 verbs during baseline or (2)
early word combination targets if they
used .50 total words but were not
combining words regularly. Second,
caregivers were taught the language
facilitation strategies in sequential
order. Performance was measured and
instruction continued to criterion
performance levels established for
each strategy. A new strategy was
taught after the caregiver reached
criterion levels on the previous
strategy. Criterion levels are provided
in Fig 1.
Trained interventionists provided the
caregiver instruction. The 2
interventionists received 30 hours of
individual instruction from M.Y.R. and
practiced implementing the child
intervention and the caregiver
instruction over a 6-month period
before beginning the intervention.
Fidelity of the implementation of the
intervention delivered by the
interventionists was recorded for
20% of sessions. The average fidelity
was 94% and exceeded 90% for all
intervention components across all
sessions.
Outcomes
Table 2 shows the primary and
secondary caregiver and child
outcomes. All outcome data were
collected at baseline and immediately
after the end of intervention
(∼3 months). Outcomes were
assessed in a clinic by a speech
language pathologist or a special
education teacher trained to fidelity.
These assessors were not naïve to the
trial arm; because of the behavioral
nature of the intervention, caregivers
knew the trial arm to which they
were assigned and made comments
during assessments that indicated
their trial arm assignment. To reduce
the potential for bias, procedural
fidelity was completed for 20% of all
assessments. In addition, all norm-
referenced assessments were scored
by 2 raters. Procedural fidelity and
scoring agreement exceeded 95% for
all assessments and did not vary by
trial arm, suggesting that the
potential for bias was low.
Caregivers’use of language
facilitation strategies was measured
during a 20-minute play-based
caregiver–child interaction in which
the caregiver and child played with
a standard set of toys in the clinic.
Interactions were coded for the
caregiver strategies listed and defined
TABLE 1 Participant Characteristics at Baseline
Variable Trial Arm
Intervention Control
n45 52
Age, months 30.3 (5.0) 30.6 (5.1)
Receiving additional speech therapy 20 14
Male 82 80
Race
African American 18 13
White 78 85
Other 4 2
Having receptive and expressive delay 69 72
Income 71 000 (35 000) 60 000 (52 000)
Mother’s education
High school 39 44
Undergraduate degree 37 27
Graduate degree 24 29
Baseline scores
Cognitive skills, BSID-3
9
91.3 (8.4) 88.6 (7.6)
Expressive language, PLS-4
12
75.2 (7.9) 75.0 (7.2)
Receptive language, PLS-4
12
76.5 (17.3) 73.8 (15.2)
Expressive vocabulary, EOWPVT-3
13
60.9 (11.5) 59.8 (10.7)
Expressive vocabulary, NDW 19.0 (17.9) 17.2 (17.5)
Expressive vocabulary, MCDI
14
92.1 (105.1) 94.4 (97.2)
Data are expressed as mean (SD) or %. BSID-3, Bayley Scales of Infant Development, Third Edition; PLS-4, Preschool
Language Scale, Fourth Edition; EOWPVT-3, Expressive One-Word Picture Vocabulary Test, Third Edition; NDW, number of
different word roots in a 20-minute play interaction; MCDI, MacArthur Bates Communication Development Inventories.
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in Table 2. Reliability was calculated
for 20% of all interactions, and point-
by-point interobserver agreement
exceeded 90% for each caregiver
behavior. Caregivers in the
intervention arm completed
a questionnaire related to the
structure and content of the
intervention and their perception of
the effect of the intervention on their
children’s communication skills.
Sample Size
We anticipated that 120 toddlers
would be eligible for the trial with
10% attrition. Assuming a baseline
covariate of 0.70 between the
primary outcome measure at baseline
and at the end of intervention,
a difference of 0.43 SD could be
detected with 90 toddlers (45 in each
arm) with 80% power at the 5%
significance level.
Statistical Analyses
An intent-to-treat analysis was used
to analyze data in both randomization
arms. Mean outcomes were compared
between arms using linear regression
adjusted for the baseline measure of
the outcome variable, family income,
and child cognitive skills at baseline.
Differences in the rate of language
delay were compared by using x
2
analysis.
RESULTS
Figure 3 summarizes the flow of
participants through each stage of the
trial. Table 1 summarizes the
participant characteristics. Baseline
differences in group characteristics
were not large but generally favored
the intervention arm. As such, final
analyses were adjusted for baseline
characteristics. Of the 97 eligible
toddlers, 45 were assigned to the
intervention group and 52 to the
control group. All toddlers in the
intervention group (n= 45) and 83%
of toddlers in the control group (n=
43) were retained after the 3-month
intervention period.
Child Outcomes
The analyses provided evidence for
improvement in all measures of
receptive language. The differences in
receptive language between the
FIGURE 1
Pictorial design of the Working on Rapid Language Development trial. PLS-4, Preschool Language Scale, Fourth Edition; EOWPVT-3, Expressive One-Word
Picture Vocabulary Test, Third Edition; PPVT, Peabody Picture Vocabulary Test, Fourth Edition; NDW, number of different words in a 20-minute play
interaction; MCDI, MacArthur Bates Communication Development Inventories.
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intervention and control arms were
small, with effect sizes ranging from
0.27 to 0.35 (P= .04). Differences in
expressive language skills were not
consistent across measures. There
were only positive effects for the
observational measure of expressive
vocabulary (P= .01, effect size 0.38).
No positive effects for overall
expressive language skills, parent
report of expressive vocabulary, or
norm-referenced expressive
vocabulary were found. x
2
Analyses
indicated that toddlers in the
intervention arm were less likely to
meet the criterion for language delay
after intervention than toddlers in the
control arm (x
2
= 3.8, P= .05). After
the 3-month intervention period,
71% of toddlers in the control arm
were delayed, compared with 51% of
toddlers in the intervention arm.
Toddlers who did not receive
intervention had a 1.4 times greater
risk of having a language delay than
toddlers who received intervention.
Caregiver Outcomes
Table 3 shows that caregivers in the
intervention arm improved their use
of all language facilitation strategies.
The differences in caregiver use of
language facilitation strategies
between the intervention and control
arms were large, with effect sizes
ranging from 0.43 to 3.19 (P,.01).
There were no differences in the
amount of total stress reported by
caregivers in the intervention and
control arms (P= .15, effect size
20.16).
Intervention Evaluation
There were no known adverse events
or side effects for those children
enrolled in the intervention group.
The majority of caregivers (98%)
reported that the strategies helped
their children’s language skills. When
asked how comfortable they felt using
the strategies, 92% of caregivers
reported that they were very
comfortable and 8% were somewhat
comfortable. Caregivers reported
using the strategies an average of
17 hours per week (range 2–77 hours,
TABLE 2 Primary and Secondary Outcome Measures for the Working on Rapid Language Development Trial
Outcome Measure Description
Primary
Receptive and expressive language Preschool Language Scale, Fourth Edition
12
Expressive score: Expressive Communication subscale;
Receptive score: Auditory Comprehension subscale; both
yield a standard score of 100 (SD 15)
Caregiver use of strategies Observational coding of a 20-min play-based
caregiver-child interaction
Matched turns: percentage of adult utterances in response to
a child’s utterance; Responsiveness: percentage of child
utterances to which the adult responded; Targets:
percentage of adult utterances that contained the child’s
language target; Expansions: percentage of child utterances
to which the adult imitates and adds a word; Time Delays:
percentage of nonverbal prompting sequences that were
used correctly; Prompting: percentage of verbal prompting
sequences that were used correctly
Secondary
Caregiver stress Parenting Stress Index, Fourth Edition
15
Total Stress score
Receptive vocabulary Peabody Picture Vocabulary Test, Fourth Edition
16
Standard score with a normative mean of 100 (SD 15)
Expressive vocabulary MacArthur-Bates Communicative Development
Inventories: Words and Sentences
14
Total number of 680 words the caregiver reports that the
child says
Number of Different Word Roots Total number of different word roots the child says in a 20-min
play interaction with a research assistant
Expressive One-Word Picture Vocabulary Test,
Third Edition
13
Standard score with a normative mean of 100 (SD 15)
Presence of language delay Preschool Language Scale, Fourth Edition
12
Total standard score ,85
FIGURE 2
Video example of a parent practicing responding to and expanding child communication with
coaching from a therapist (Supplemental Video).
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SD 18). The majority of caregivers
(98%) reported teaching the
language facilitation strategies to
another caregiver. The majority of
caregivers (98%) reported that they
preferred the home and clinic
location to home only or clinic only.
Caregivers ranked the strategies they
found most helpful in the following
order: (1) responsiveness, (2)
matched turns, (3) expansions, (4)
targets, (5) prompting, and (6) time
delays. Caregivers reported that
observing the interventionist model
the strategies and practicing the
strategies with coaching from the
interventionist were the most helpful
instructional methods. The average
cost of intervention was $3861 per
child, with a range of $2767 to $5653.
Intervention costs included travel
costs ($0.55/mile) and therapist
salary ($65/hour) for time spent in
instruction, traveling, preparing for,
and delivering the intervention
sessions.
DISCUSSION
Main Findings
This is the first trial to include
specific criterion levels for caregiver
use of language facilitation strategies
and to continuously monitor
caregiver use of these strategies. High
fidelity in caregiver use of language
facilitation strategies resulted in
FIGURE 3
Participant flow chart for the Working on Rapid Language Development trial.
TABLE 3 Outcome Comparisons
Outcome Mean (SD) for Trial Arms Adjusted
Intervention
(n= 45)
Control
(n= 43)
Mean Difference
(Intervention 2Control)
95% Confidence
Interval
PEffect Size
Primary child outcomes
Expressive language, PLS-4
12
84.0 (13.9) 80.2 (12.0) 0.37 24.5 to 5.3 .88 0.03
Receptive language, PLS-4
12
86.3 (19.4) 77.3 (20.4) 5.3 0.15 to 10.4 .04 0.27
Secondary child outcomes: Expressive Vocabulary
MCDI
14
263.7 (172.6) 214.5 (146.3) 32.8 217.3 to 83.0 .20 0.21
NDW 54.9 (30.2) 38.0 (30.3) 11.4 2.5 to 20.4 .01 0.38
EOWPVT-3
13
75.7 (16.3) 70.0 (17.7) 3.5 24.2 to 11.12 .40 0.21
Secondary child outcomes: Receptive Vocabulary
PPVT-4
16
94.3 (13.6) 85.6 (16.7) 5.3 0.4 to 10.5 .04 0.35
Primary caregiver outcomes, %
Matched turns 74 (13) 32 (15) 40 34 to 46 ,.01 2.86
Responsiveness 85 (9) 80 (14) 5 1 to 10 .05 0.43
Targets 47 (21) 3 (4) 39 33 to 45 ,.01 2.55
Expansions 42 (18) 4 (4) 42 35 to 48 ,.01 3.19
Time delays 42 (38) 0 (0) 29 18 to 40 ,.01 1.07
Prompting 50 (38) 3 (9) 35 17 to 53 ,.01 1.25
Secondary caregiver outcomes
Stress, PSI
15
194.2 (43.4) 216.6 (38.2) 26.7 216 to 2.6 .15 20.16
Effect size calculated by dividing the adjusted mean difference by the pooled SD of the intervention and control arms. Adjusted analyses include baseline scores, household income, and child
cognitive scores as covariates. PLS-4, Preschool Language Scale, Fourth Edition; MCDI, MacArthur Bates Communication Development Inventories; NDW, number of different words in a 20-minute
play interaction; EOWPVT-3, Expressive One-Word Picture Vocabulary Test, Third Edition; PPVT, Peabody Picture Vocabulary Test, Fourth Edition; PSI, Parenting Stress Index, Fourth Edition.
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small benefits to receptive language
but not to the primary expressive
language outcome, although 1 of the 3
expressive vocabulary measures did
seem to benefit. These results differ
from previous studies,
7,8
which did
not report positive expressive
language outcomes. Toddlers in the
intervention arm used 11 more
different words in a 20-minute
structured play interaction than
toddlers in the control arm. However,
differences between the intervention
and control arms were not observed
for other measures of expressive
language skills. Given the relatively
brief nature of the intervention
(3 months), it is not surprising that
only changes in the proximal measures
were evident immediately after the
end of intervention. Over time,
changes in these proximal measures
(number of different words in the
language sample) may result in
changes in the distal measures
(norm-referenced tests) of expressive
language. These positive outcomes
were achieved during 28 intervention
sessions over the course of the 3-
month intervention with a total
delivery cost of $3861 per family.
This cost and limited duration of
intervention are relatively modest
given the promising results.
Strengths
The components of the intervention
were naturalistic language facilitation
strategies similar to those commonly
used in speech-language therapy and
early intervention. Caregivers rated
the intervention strategies as easy to
use throughout the day. The
intervention approach was
individualized to accommodate
different rates of caregiver learning
and child targets, yet standardized
sufficiently that all caregivers and
children received the same
intervention. The length and frequency
of the intervention were compatible
with community-based early
intervention service delivery models.
Unique features of this trial include
systematic and continuous monitoring
of caregiver use of language facilitation
strategies, inclusion of children with
receptive and expressive language
delays, and a standardized protocol for
teaching caregivers.
The research design included random
assignment, low attrition, and careful
and continuous monitoring of
caregiver use of the language
facilitation strategies. Intervention
fidelity was measured for the
therapist and for the caregiver,
ensuring a high level of quality
control. The manualized intervention
program included a replicable yet
individualized protocol. Taken
together, these methodological
strengths indicate high internal and
external validity, increasing the
likelihood that these positive results
will generalize to similar samples.
Limitations
The current findings should be
considered in the context of several
limitations. First, the long-term
outcomes remain unknown. Longer-
term outcome measures may produce
different results. Follow-up is ongoing
and will provide additional information
about spontaneous recovery rates and
maintenance of language facilitation
strategies by caregivers. Second, the
majority of participants were from
mainstream US cultures. Thus, it is
unclear whether the results of this
study would generalize to caregivers
from other cultures with different
beliefs about child-rearing practices.
14
Third, participant recruitment took
place over 4 years and included
a variety of sources (self-referral,
pediatrician referral, early intervention
referral). It is possible that families
who chose to participate in a research
study may have been more motivated
than families from the general
population. Fourth, because assessors
and caregivers could not remain naïve
to the trial arm, the potential for bias
exists.
Interpretation
The instruction to caregivers had the
greatest effects on matched turns,
targets, and expansions. These
language facilitation strategies in
turn had the largest impact on
receptive language skills and
expressive vocabulary. Results of this
study have several important clinical
implications. Children with
expressive and receptive language
delays are likely to benefit from early
intervention. This is the second trial
to find positive effects on expressive
vocabulary outcomes for toddlers
with receptive and expressive
language delays.
6
Results from the
current trial indicate that the effects
of early intervention may be
maximized when the caregiver is
included in the intervention.
Teaching caregivers to use language
facilitation strategies is a cost-
effective way to provide early
intervention to this population.
However, teaching caregivers is
a complex process that requires
ongoing monitoring and coaching.
The current trial is the first step in
investigating effective interventions
for a population of children with
language delays who are at risk for
persistent communication
difficulties.
CONCLUSIONS
Given the long-term negative
academic and social effects of
persistent communication difficulties,
the outcomes of this trial provide
preliminary support for early
intervention for toddlers with
language delays. This trial provides
rigorous evidence of the effects of
systematic instruction to caregivers
on their use of language facilitation
strategies and subsequent changes in
their children’s receptive and
expressive language skills. The
outcomes are particularly promising
given the modest cost and limited
duration of the intervention. Long-
term follow-up of intervention effects
is ongoing and will assess the long-
term impact of early intervention on
child language skills. Whereas
caregiver use of language facilitation
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strategies resulted in positive
receptive language and some
expressive vocabulary outcomes, the
amount and total dosage of caregiver
strategy use needed to optimize
language outcomes remains
unknown. Future research should
investigate specific caregiver
language facilitation strategies and
the amount of caregiver strategy use
that maximizes child language
outcomes.
FINANCIAL DISCLOSURE: The authors have indicated they have no financial relationships relevant to this article to disclose.
FUNDING: Supported by grant R324A090181 from the Institute of Education Sciences and UL1 TR000445 from the National Center for Advancing Translational
Sciences, NIH. Funded by the National Institutes of Health (NIH).
POTENTIAL CONFLICT OF INTEREST: The authors have indicated they have no potential conflicts of interest to disclose.
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DOI: 10.1542/peds.2014-2134
; originally published online March 2, 2015; 2015;135;686Pediatrics Megan Y. Roberts and Ann P. Kaiser
Controlled Trial
Early Intervention for Toddlers With Language Delays: A Randomized
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