Scolaris Content Display Scolaris Content Display

Study flow diagram.
Figures and Tables -
Figure 1

Study flow diagram.

Risk of bias graph: review authors' judgements about each risk of bias item presented as percentages across all included studies.
Figures and Tables -
Figure 2

Risk of bias graph: review authors' judgements about each risk of bias item presented as percentages across all included studies.

Risk of bias summary: review authors' judgements about each risk of bias item for each included study.
Figures and Tables -
Figure 3

Risk of bias summary: review authors' judgements about each risk of bias item for each included study.

Forest plot of comparison: 1 Adaptive behavior, outcome: 1.1 Vineland Adaptive Behavior Scales Composite
Figures and Tables -
Figure 4

Forest plot of comparison: 1 Adaptive behavior, outcome: 1.1 Vineland Adaptive Behavior Scales Composite

Comparison 1 Early intensive behavioral intervention (EIBI) compared to for young children with autism spectrum disorders (ASD), Outcome 1 Adaptive behavior.
Figures and Tables -
Analysis 1.1

Comparison 1 Early intensive behavioral intervention (EIBI) compared to for young children with autism spectrum disorders (ASD), Outcome 1 Adaptive behavior.

Comparison 1 Early intensive behavioral intervention (EIBI) compared to for young children with autism spectrum disorders (ASD), Outcome 2 Autism symptom severity.
Figures and Tables -
Analysis 1.2

Comparison 1 Early intensive behavioral intervention (EIBI) compared to for young children with autism spectrum disorders (ASD), Outcome 2 Autism symptom severity.

Comparison 1 Early intensive behavioral intervention (EIBI) compared to for young children with autism spectrum disorders (ASD), Outcome 3 Intelligence.
Figures and Tables -
Analysis 1.3

Comparison 1 Early intensive behavioral intervention (EIBI) compared to for young children with autism spectrum disorders (ASD), Outcome 3 Intelligence.

Comparison 1 Early intensive behavioral intervention (EIBI) compared to for young children with autism spectrum disorders (ASD), Outcome 4 Communication skills.
Figures and Tables -
Analysis 1.4

Comparison 1 Early intensive behavioral intervention (EIBI) compared to for young children with autism spectrum disorders (ASD), Outcome 4 Communication skills.

Comparison 1 Early intensive behavioral intervention (EIBI) compared to for young children with autism spectrum disorders (ASD), Outcome 5 Language skills.
Figures and Tables -
Analysis 1.5

Comparison 1 Early intensive behavioral intervention (EIBI) compared to for young children with autism spectrum disorders (ASD), Outcome 5 Language skills.

Comparison 1 Early intensive behavioral intervention (EIBI) compared to for young children with autism spectrum disorders (ASD), Outcome 6 Social competence.
Figures and Tables -
Analysis 1.6

Comparison 1 Early intensive behavioral intervention (EIBI) compared to for young children with autism spectrum disorders (ASD), Outcome 6 Social competence.

Comparison 1 Early intensive behavioral intervention (EIBI) compared to for young children with autism spectrum disorders (ASD), Outcome 7 Daily living skills.
Figures and Tables -
Analysis 1.7

Comparison 1 Early intensive behavioral intervention (EIBI) compared to for young children with autism spectrum disorders (ASD), Outcome 7 Daily living skills.

Comparison 1 Early intensive behavioral intervention (EIBI) compared to for young children with autism spectrum disorders (ASD), Outcome 8 Problem behavior.
Figures and Tables -
Analysis 1.8

Comparison 1 Early intensive behavioral intervention (EIBI) compared to for young children with autism spectrum disorders (ASD), Outcome 8 Problem behavior.

Study

EIBI N

EIBI N for general education with no extra support

EIBI N for general education with support

TAU N

TAU N for general education with no extra support

TAU N for general education with support

Cohen 2006

21

6

11

21

0

1

Smith 2000

15

4

2

13

0

3

Figures and Tables -
Analysis 1.9

Comparison 1 Early intensive behavioral intervention (EIBI) compared to for young children with autism spectrum disorders (ASD), Outcome 9 Academic placement.

Comparison 1 Early intensive behavioral intervention (EIBI) compared to for young children with autism spectrum disorders (ASD), Outcome 10 Parent stress.
Figures and Tables -
Analysis 1.10

Comparison 1 Early intensive behavioral intervention (EIBI) compared to for young children with autism spectrum disorders (ASD), Outcome 10 Parent stress.

Summary of findings for the main comparison. Early intensive behavioral intervention (EIBI) for young children with autism spectrum disorders (ASD)

Early intensive behavioral intervention (EIBI) for young children with autism spectrum disorders (ASD)

Patient or population: patients with young children (less than six years old) with autism spectrum disorders (ASD)
Settings: family's homes
Intervention: early intensive behavioral intervention (EIBI)
Comparison: treatment as usual (TAU)

Outcomes

Illustrative comparative risks* (95% CI)

Relative effect
(95% CI)

Number of participants
(studies)

Quality of the evidence
(GRADE)

Comments

Assumed risk

Corresponding risk

TAU

EIBI

Adaptive behavior
Measured by: Vineland Adaptive Behavior Scales (parent‐reported scale; mean = 100 (SD = 15); higher score equates to better outcomes)
Follow‐up: 2 to 3 years

The mean adaptive behavior score ranged across control groups from

48.60 points to 67.10 points

The mean adaptive behavior score in the intervention groups was, on average, 9.58 points higher (5.57 points higher to 13.6 points higher)

202
(5 studies)

⊕⊕⊝⊝
Low1,2,3

Autism symptom severity
Measured by: parent‐reported autism symptoms on standardised autism screening and diagnostic instruments (lower scores indicate less severe autism symptoms)
Follow‐up: 2 years

The mean autism symptom severity score in the intervention groups was 0.34 standard deviations lower
(0.79 standard deviations lower to 0.11 standard deviations higher)

81
(2 studies)

⊕⊝⊝⊝
Very low3,4

General guidelines for the magnitude of an effect suggest that effect sizes of 0.20 to 0.50 are considered to have a small effect, effect sizes of 0.50 to 0.80 are considered to have a medium effect, and effect sizes greater than 0.80 are considered to have a large effect (Cohen 1988)

Adverse effects

Measured by: worsening of adaptive behavior or autism symptom severity

Follow‐up: 2 to 3 years

No adverse events were reported in any study

Intelligence
Measured by: standardized IQ tests (mean = 100 (SD = 15); higher scores indicate higher IQ)
Follow‐up: 2 to 3 years

The mean IQ score ranged across control groups from

49.67 points to 73.20 points

The mean IQ score in the intervention groups was, on average, 15.44 higher (9.29 points higher to 21.59 points higher)

202
(5 studies)

⊕⊕⊝⊝
Low1,2,3

Communication and language skills: expressive language
Measured by: standardized measures of expressive language (higher scores indicate better expressive language skills)
Follow‐up: 2 to 3 years

The mean expressive language score in the intervention groups was 0.51 standard deviations higher
(0.12 standard deviations higher to 0.90 standard deviations higher)

165
(4 studies)

⊕⊕⊝⊝
Low1,3,5

General guidelines for the magnitude of an effect suggest that effect sizes of 0.20 to 0.50 are considered to have a small effect, effect sizes of 0.50 to 0.80 are considered to have a medium effect, and effect sizes greater than 0.80 are considered to have a large effect (Cohen 1988)

Communication and language skills: receptive language
Measured by: standardized measures of receptive language (higher scores indicate better receptive language skills)
Follow‐up: 2 ‐ 3 years

The mean receptive language score in the intervention groups was 0.55 standard deviations higher (0.23 standard deviations higher to 0.87 standard deviations higher)

164
(4 studies)

⊕⊕⊝⊝
Low1,3,5

General guidelines for the magnitude of an effect suggest that effect sizes of 0.20 to 0.50 are considered to have a small effect, effect sizes of 0.50 to 0.80 are considered to have a medium effect, and effect sizes greater than 0.80 are considered to have a large effect (Cohen 1988)

Problem behavior
Measured by: standardized parent‐report measures and checklists (lower scores indicate lower levels or less severe problem behavior)
Follow‐up: 2 to 3 years

The mean problem behavior score in the intervention groups was 0.58 standard deviations lower (1.24 standard deviations lower to 0.07 standard deviations higher)

67
(2 studies)

⊕⊝⊝⊝
Very low3,6

General guidelines for the magnitude of an effect suggest that effect sizes of 0.20 to 0.50 are considered to have a small effect, effect sizes of 0.50 to 0.80 are considered to have a medium effect, and effect sizes greater than 0.80 are considered to have a large effect (Cohen 1988)

*The basis for the assumed risk (e.g. the median control group risk across studies) is provided in footnotes. The corresponding risk (and its 95% CI) is based on the assumed risk in the comparison group and the relative effect of the intervention (and its 95% CI).

ASD: autism spectrum disorders; CCT: clinical controlled trial; CI: Confidence interval; EIBI: early intensive behavioral intervention; IQ: intelligence quotient; RCT: randomized controlled trial

GRADE Working Group grades of evidence
High quality: Further research is very unlikely to change our confidence in the estimate of effect.
Moderate quality: Further research is likely to have an important impact on our confidence in the estimate of effect and may change the estimate.
Low quality: Further research is very likely to have an important impact on our confidence in the estimate of effect and is likely to change the estimate.
Very low quality: We are very uncertain about the estimate.

1One study was conducted using an RCT design (Smith 2000) and four studies were conducted using a CCT design (Cohen 2006; Howard 2014; Magiati 2007; Remington 2007). Quality of evidence rating downgraded two levels due to inclusion of non‐randomized studies and associated risks of bias.
2Outcome collected in four of five studies by assessors who were blind to treatment status of participants.
3Small number of included studies precludes our ability to examine funnel plot and thereby cannot exclude the potential of publication bias.
4Both studies were conducted using a CCT design (Magiati 2007; Remington 2007). Quality of evidence rating downgraded three levels due to inclusion of non‐randomized studies, associated risks of bias, and small number of included studies.
5Outcomes collected in three of the four studies by assessors who were blind to treatment status of participants.
6One study was conducted using a RCT design (Smith 2000) and one study was conducted using a CCT design (Remington 2007). Quality of evidence rating downgraded three levels due to inclusion of non‐randomized studies and associated risks of bias and a small number of included studies.

Figures and Tables -
Summary of findings for the main comparison. Early intensive behavioral intervention (EIBI) for young children with autism spectrum disorders (ASD)
Table 1. Outcome assessments and time points measured by studies

 

 

Treatment Groups

Comparison Groups

Study

Outcomes

Pre‐Treatment

Post‐Treatment

Pre‐Treatment

Post‐Treatment

Cohen 2006

Primary

Adaptive behavior

VABS composite

VABS composite

VABS composite

VABS composite

Autism severity

NA

NA

NA

NA

Secondary

IQ

BSID‐II; WPPSI‐R

BSID‐II; WPPSI‐R

BSID; WPPSI‐R

BSID‐II; WPPSI‐R

Non‐verbal IQ

MPS

MPS

MPS

MPS

Non‐verbal social communication

NA

NA

NA

NA

Expressive communication

RDLS

RDLS

RDLS

RDLS

Receptive communication

RDLS

RDLS

RDLS

RDLS

Play

NA

NA

NA

NA

Social competence

VABS socialization domain

VABS socialization domain

VABS socialization domain

VABS socialization domain

Daily living skills

VABS daily living skills domain

VABS daily living skills domain

VABS daily living skills domain

VABS daily living skills domain

Academic achievement

NA

NA

NA

NA

Problem behavior

NA

NA

NA

NA

Parent stress

NA

NA

NA

NA

Academic placement

NA

Class placement

NA

Class placement

Quality of life

NA

NA

NA

NA

Howard 2014

Primary

Adaptive behavior

VABS composite; Denver; DP‐II; RIDES

VABS composite; Denver; DP‐II; RIDES

VABS composite

VABS composite

Autism severity

# of DSM‐IV criteria (APA 1994)

NA

# of DSM‐IV criteria

NA

Secondary

IQ

WPPSI‐R; BSID‐II; S‐B; DAYC; PEP‐R; DAS; DP‐II

WPPSI‐R, BSID‐II, S‐B; DAYC, PEP‐R, DAS

WPPSI‐R, BSID‐II, S‐B; DAS

WPPSI‐R, BSID‐II, S‐B; DAS

Non‐verbal IQ

MPS; S‐B

MPS; S‐B; Leiter‐R

MPS; S‐B

MPS; S‐B; Leiter‐R

Non‐verbal social communication

NA

NA

NA

NA

Expressive communication

RDLS; ITLS; REEL‐R; PLS‐3; ITDA; EVT; DP‐II

RDLS; ITLS; REEL‐R; PLS‐3; ITDA; EVT; EOWPVT

RDLS; ITLS; REEL‐R; PLS‐3; ITDA; EVT; DP‐II

RDLS; ITLS; REEL‐R; PLS‐3; ITDA; EVT; EOWPVT

Receptive communication

RDLS; ITLS; REEL‐R; PLS‐3; ITDA; PPVT‐III; DP‐II

RDLS; ITLS; REEL‐R; PLS‐3; PPVT‐III; ROWPVT; ITDA‐1

RDLS; ITLS; REEL‐R; PLS‐3; PPVT‐III; DP‐II; ITDA‐1

RDLS; ITLS; REEL‐R; PLS‐3; PPVT‐III, ROWPVT; ITDA‐1

Play

NA 

 NA

 NA

 NA

Social competence

VABS socialization domain

VABS socialization domain

VABS socialization domain

VABS socialization domain

Daily living skills

VABS daily living skills domain

VABS daily living skills domain

VABS daily living skills domain

VABS daily living skills domain

Academic achievement

NA

NA

NA

NA

Problem behavior

NA

NA

NA

NA

Parent stress

NA

NA

NA

NA

Academic placement

NA

NA

NA

NA

Quality of life

NA

 NA

 NA

 NA

Magiati 2007

Primary

Adaptive behavior

VABS composite

VABS composite

VABS composite

VABS composite

Autism severity

ADI‐R

ADI‐R

ADI‐R

ADI‐R

Secondary

IQ

WPPSI‐R; BSID‐R; MPS

WPPSI‐R; BSID‐R; MPS

WPPSI‐R; BSID‐R; MPS

WPPSI‐R; BSID‐R; MPS

Non‐verbal IQ

NA

NA

NA

NA

Non‐verbal social communication

NA

NA

NA

NA

Expressive communication

EOWPVT‐R

EOWPVT‐R

EOWPVT‐R

EOWPVT‐R

Receptive communication

BPVS‐II

BPVS‐II

BPVS‐II

BPVS‐II

Play

SPT‐II

SPT‐II

SPT‐II

SPT‐II

Social competence

VABS socialization domain

VABS socialization domain

VABS socialization domain

VABS socialization domain

Daily living skills

VABS daily living skills domain

VABS daily living skills domain

VABS daily living skills domain

VABS daily living skills domain

Academic achievement

NA

NA

NA

NA

Problem behavior

NA

NA

NA

NA

Parent stress

NA

NA

NA

NA

Academic placement

NA

NA

NA

NA

Quality of life

NA

NA

NA

NA

Remington 2007

Primary

Adaptive behavior

VABS composite

VABS composite

VABS composite

VABS composite

Autism severity

ASQ

ASQ

ASQ

ASQ

Secondary

IQ

BSID‐R; S‐B

BSID‐R; S‐B

BSID‐R; S‐B

BSID‐R; S‐B

Non‐verbal IQ

NA

NA

NA

NA

Non‐verbal social communication

ESCS

ESCS

ESCS

ESCS

Expressive communication

RDLS

RDLS

RDLS

RDLS

Receptive communication

RDLS

RDLS

RDLS

RDLS

Play

NA

NA

NA

NA

Social competence

VABS socialization domain

VABS socialization domain

VABS socialization domain

VABS socialization domain

Daily living skills

VABS daily living skills domain

VABS daily living skills domain

VABS daily living skills domain

VABS daily living skills domain

Academic achievement

NA

NA

NA

NA

Problem behavior

DCBC

DCBC

DCBD

DCBD

Parent stress

QRS‐F parent and family problems subscale

QRS‐F parent and family problems subscale

QRS‐F parent and family problems subscale

QRS‐F parent and family problems subscale

Academic placement

NA

NA

NA

NA

Quality of life

NA

NA

NA

NA

Smith 2000

Primary

Adaptive behavior

VABS composite

VABS composite

VABS composite

VABS composite

Autism severity

NA

NA

NA

NA

Secondary

IQ

BSID‐R; S‐B

BSID‐R; S‐B

BSID‐R; S‐B

BSID‐R; S‐B

Non‐verbal IQ

MPS

MPS

MPS

MPS

Non‐verbal social communication

NA

NA

NA

NA

Expressive communication

RDLS

RDLS

RDLS

RDLS

Receptive communication

RDLS

RDLS

RDLS

RDLS

Play

NA

NA

NA

NA

Social competence

VABS socialization domain

VABS socialization domain

VABS socialization domain

VABS socialization domain

Daily living skills

VABS daily living skills domain

VABS daily living skills domain

VABS daily living skills domain

VABS daily living skills domain

Academic achievement

WIAT; ELM

WIAT

WIAT

WIAT

Problem behavior

CBCL

CBCL

CBCL

CBCL

Parent stress

NA

NA

NA

NA

Academic placement

Class placement

Class placement

Class placement

Class placement

Quality of life

NA

NA

NA

NA

ADI‐R: Autism Diagnostic Interview ‐ Revised (Lord 1994)
ASQ: Autism Screening Questionnaire (Berument 1999)
BPVS‐II: British Picture Vocabulary Scale ‐ 2nd Edition (Dunn 1997b)
BSID‐II: Bayley Scales of Infant Development ‐ 2nd Edition (Bayley 1993)
CBCL: Child Behavior Checklist (Achenbach 1991)
DAS: Differential Ability Scales (Elliot 1990)
DAYC: Developmental Assessment of Young Children (Voress 1998)
DBC: Developmental Behavior Checklist (Einfeld 1995)
Denver: Denver Developmental Screening Test (Frankenbrug 1992)
DP‐II: Developmental Profile ‐ 2nd Edition (Alpern 1986)
DSM‐IV: Diagnostic and Statistical Manual of Mental Disorders ‐ 4th Edition (APA 1994)
ELM: Early Learning Measure (Smith 1995)
EOWPVT‐R: Expressive One‐Word Picture Vocabulary Test (Brownell 2000a)
EOWPVT‐R: Expressive One‐Word Picture Vocabulary Test ‐ Revised (Gardner 1990)
ESCS:Early Social Communication Scales (Mundy 1996)
EVT:Expressive Vocabulary Test (Williams 1997)
ITDA:Infant‐Toddler Developmental Assessment (Provence 1985)
ITLS: Infant‐Toddle Language Scale (Rosetti 1990)
IQ: intelligence quotient
Leiter‐R: Leiter International Performance Scale ‐ Revised (Roid 1997)
MPS: Merrill‐Palmer Scale of Mental Tests (Stutsman 1948)
NA: not assessed
NCBRF: Nisonger Child Behavior Rating Form (Tasse 1996)
PEP‐R: Psychoeducational Profile ‐ Revised (Schopler 1990)
PLS‐3:Preschool Language Scale — 3rd Edition (Zimmerman 1992)
PPVT‐III:Peabody Picture Vocabulary Test —3rd Edition (Dunn 1997a)
QRS‐F: Questionnaire on Resources and Stress‐Friedrich, Short Form (Friedrich 1983)
RDLS: Reynell Developmental Language Scales (Reynell 1990)
ROWPVT: Receptive One‐Word Picture Vocabulary Test (Brownell 2000b)
REEL‐R:Receptive Expressive Emergent Language scales — Revised (Bzoch 1991)
RIDES: Rockford Infant Developmental Evaluation Scales (Project RHISE 1979)
S‐B: Stanford‐Binet Intelligence Scale — 4th Edition (Thorndike 1986)
SPT‐II: Symbolic Play Test — 2nd Edition (Lowe 1988)
VABS: Vineland Adaptive Behavior Scales (Sparrow 1984)
WIAT: Weschler Individual Achievement Test (Weschler 1992)
WWPSI‐R: Weschler Preschool and Primary Scale of Intelligence — Revised (Wechsler 1989)

Figures and Tables -
Table 1. Outcome assessments and time points measured by studies
Table 2. Assessment of risk of bias

'Risk of bias' item

Question

How risk of bias was assessed

Sequence generation

Was the sequence generation method used adequate?

We judged the risk of bias as follows:

  1. 'low' ‐ when participants were allocated to treatment conditions using randomization such as computer‐generated random numbers, a random numbers table, or coin‐tossing;

  2. 'unclear' ‐ when the randomization method was not clearly stated or unknown; or

  3. 'high' ‐ when randomization did not use any of the above methods.

Allocation concealment

Was allocation adequately concealed?

We judged the risk of bias as follows:

  1. 'low' ‐ when participants and researchers were unaware of participants' future allocation to treatment condition until after decisions about eligibility were made and informed consent was obtained;

  2. 'unclear' ‐ when allocation concealment was not clearly stated or unknown; or

  3. 'high' ‐ when allocation was not concealed from either participants before informed consent or from researchers before decisions about inclusion were made, or allocation concealment was not used.

Blinding of participants and personnel

Were participants and personnel blind to which participants were in the treatment group?

We judged the risk of bias as follows:

  1. 'low' ‐ when blinding of participants and key personnel was ensured;

  2. 'unclear' ‐ when blinding of participants and key personnel was not reported; or

  3. 'high' ‐ when there was no or incomplete blinding of participants and key personnel or blinding of participants and key personnel was attempted but likely to have been broken.

Blinding of outcome assessment

Were outcome assessors blind to which participants were in the treatment group?

We judged the risk of bias as follows:

  1. 'low' ‐ when blinding of outcome assessment was ensured;

  2. 'unclear' ‐ when there was not adequate information provided in the study report to determine blinding of outcome assessment, or blinding of outcome assessment was not addressed; or

  3. 'high' ‐ when blinding of outcome assessment was not ensured.

Incomplete outcome data

Did the trial authors deal adequately with missing data?

We judged the risk of bias as follows:

  1. 'low' ‐ when the numbers of participants randomized to groups is clear and it is clear that all participants completed the trials;

  2. 'unclear' ‐ when information about which participants completed the study could not be acquired by contacting the researchers of the study; or

  3. 'high' ‐ when there was clear evidence that there was attrition or exclusion from analysis in at least one participant group that was likely related to the true outcome.

Selective outcome reporting

Did the authors of the trial omit to report on any of their outcomes?

We judged the risk of bias as follows:

  1. 'low' ‐ when it is clear that the published report includes all expected outcomes;

  2. 'unclear' ‐ when it is not clear whether other data were collected and not reported; or

  3. 'high' ‐ when the data from one or more expected outcomes were missing.

Protection against contamination

Could the control group also have received the intervention?

We judged the risk of bias as follows:

  1. 'low' ‐ when allocation was by community, institution or school, and it is unlikely that the control group received the intervention;

  2. 'unclear' ‐ when professionals were allocated within a clinic or school and it is possible that the communication between intervention and control professionals could have occurred; or

  3. 'high' ‐ when it is likely that the control group received part of the intervention.

Baseline measurements

Were the intervention and control groups similar at baseline for chronological age, IQ, adaptive behavior skills, and communication skills?

We judged the risk of bias as follows:

  1. 'low' ‐ when participant performance on outcomes were measured prior to the intervention and no important differences were present across study groups;

  2. 'unclear' ‐ when no baseline measures of outcome were reported or it was difficult to determine if baseline measures were substantially different across study groups; or

  3. 'high' ‐ when important differences were present and were likely to undermine any post‐intervention difference.

Other potential sources of bias

Through assessment, we determined whether any other source of bias was present in the trial, such as changing methods during the trial, or other anomalies.

We judged the risk of bias as follows:

  1. 'low' ‐ when no other sources of bias were detected;

  2. 'unclear' ‐ when additional sources of bias were suspected but could not be confirmed; or

  3. 'high' ‐ when other sources of bias were clearly present and likely to contribute to post‐intervention differences.

IQ: intelligence quotient

Figures and Tables -
Table 2. Assessment of risk of bias
Table 3. Additional methods that were not used

Analysis

Description of method

Reason not used

Measurement of treatment effect

Continuous data

If outcomes are measured on a consistent scale across studies, we will calculate the effect of each study using the mean difference effect size.

As we needed to use the standardized mean difference (SMD) across most outcomes, we decided to report all effect sizes using the SMD effect size.

Dichotomous data

If we locate dichotomous data, we will calculate a risk ratio with a 95% confidence interval for each outcome in each trial (Deeks 2017).

We did not locate dichotomous data.

Unit of analysis issues

Cluster‐randomized trials

If we locate cluster‐randomized trials, we will analyze them in accordance with the methods outlined in the Cochrane Handbook for Systematic Reviews of Interventions (Higgins 2011, 16.3).

We did not find cluster‐randomized trials.

Multiple treatment groups

If we locate data from studies with multiple treatment groups, we will analyze each intervention group separately by dividing the sample size for the common comparator groups proportionately across each comparison (Higgins 2011, 16.5.5).

Assessment of reporting bias

If we identify 10 or more studies, we will draw funnel plots (estimated differences in treatment effects against their standard error). Asymmetry could be due to publication bias, but could also be due to a real relation between trial and effect size, such as when larger trials have lower compliance and compliance is positively related to effect size (Sterne 2011). If we find such a relation, we will examine clinical variation between the studies (Sterne 2011, 10.4). As a direct test for publication bias, we will conduct sensitivity analyses to compare the results from published data with data from other sources. We will do a funnel plot in an update of the review if enough additional trials are located.

We did not locate enough studies to assess reporting bias.

Subgroup analyses

If we locate enough trials, we will examine possible clinical and methodological heterogeneity using subgroup analyses. The possible subgroups that we will examine, if present, are: intervention density (intensity) and duration; type of comparison group (for example, home‐based TAU, school‐based TAU, no treatment control), and pre‐treatment participant characteristics (for example, chronological age, symptom severity, IQ, communicative ability, and level of adaptive behavior).

We did not conduct subgroup analyses due to the small number of included trials.

Sensitivity analyses

If we locate enough trials, we will explore the impact of studies with high risk of bias on the robustness of the results of the review in sensitivity analyses by removing studies with a high risk of bias on baseline measurements and blinding of outcome assessment, and reanalyzing the remaining studies to determine whether these factors affected the results.

We did not conduct sensitivity analyses due to the small number of included trials.

CCTs: controlled clinical trials
CI: confidence interval
IQ: intelligence quotient
TAU: treatment as usual

Figures and Tables -
Table 3. Additional methods that were not used
Comparison 1. Early intensive behavioral intervention (EIBI) compared to for young children with autism spectrum disorders (ASD)

Outcome or subgroup title

No. of studies

No. of participants

Statistical method

Effect size

1 Adaptive behavior Show forest plot

5

202

Mean Difference (IV, Random, 95% CI)

9.58 [5.57, 13.60]

2 Autism symptom severity Show forest plot

2

81

Std. Mean Difference (IV, Random, 95% CI)

‐0.34 [‐0.79, 0.11]

3 Intelligence Show forest plot

5

202

Mean Difference (IV, Random, 95% CI)

15.44 [9.29, 21.59]

4 Communication skills Show forest plot

5

201

Mean Difference (IV, Random, 95% CI)

11.22 [5.39, 17.04]

5 Language skills Show forest plot

4

Std. Mean Difference (IV, Random, 95% CI)

Subtotals only

5.1 Expressive language

4

165

Std. Mean Difference (IV, Random, 95% CI)

0.51 [0.12, 0.90]

5.2 Receptive language

4

164

Std. Mean Difference (IV, Random, 95% CI)

0.55 [0.23, 0.87]

6 Social competence Show forest plot

5

201

Mean Difference (IV, Random, 95% CI)

6.56 [1.52, 11.61]

7 Daily living skills Show forest plot

5

201

Mean Difference (IV, Random, 95% CI)

7.77 [3.75, 11.79]

8 Problem behavior Show forest plot

2

67

Std. Mean Difference (IV, Random, 95% CI)

‐0.58 [‐1.24, 0.07]

9 Academic placement Show forest plot

Other data

No numeric data

10 Parent stress Show forest plot

1

Std. Mean Difference (IV, Random, 95% CI)

Totals not selected

Figures and Tables -
Comparison 1. Early intensive behavioral intervention (EIBI) compared to for young children with autism spectrum disorders (ASD)