Wang and colleagues «Wang X, Zhao J, Huang S ym. Cognitive Behavioral T...»1 aimed to evaluate the effectiveness of CBT on the symptoms related to ASD and social-emotional problems in children or adolescents with ASD in their meta-analysis. Data sources PubMed, Embase, and the Cochrane Library were systematically searched for studies that were published from their inception until May 2019. Researchers selected randomized controlled trials (RCTs) in which effectiveness of CBT on the symptoms of ASD and social-emotional problems in children or adolescents with ASD was reported. Finally, 45 RCTs and 6 quasi RCTs were selected for the meta-analysis. 9 to 196 patients were included in each trial.
A total of 2485 children and adolescents diagnosed with ASDs were included in this meta-analysis. Participants were under 18 years of age, mean age varying between 5.3 to 15 years for the CBT-group and 5.2 to 15.56 years for the control group.
Interventions included different kinds of CBT interventions which contained both cognitive and behavioral components. Of the interventions 31 were group-based, 18 had individual sessions and 2 interventions consisted of both group-based and individual sessions. The number of sessions varied between 6 to 32.
Symptoms related to ASD (social communication, social cognition, social awareness, social motivation, assertion, cooperation, responsibility, autistic mannerisms, and the frequency of peer interactions) were evaluated based on self-reported outcomes, informant reported outcomes, clinician-rated outcomes, and task-based outcomes. Social-emotional problems were evaluated based on self-reported outcomes, informant-reported outcomes, and clinician-rated outcomes.
There was no significant difference between CBT and control groups (10 trials) regarding symptoms related to ASD based on self-reported outcomes (SMD: -0.09; 95% CI: -0.42 to 0.24; P = .593). CBT significantly improved the symptoms related to ASD based on informant-reported outcomes (23 trials, SMD -0.57; 95%CI: -0.90 to -0.24; P= .001), clinician-rated outcomes (5 trials, SMD: 0.75; 95% CI: 0.10 to 1.41; P = .024) and task-based outcomes (11 trials, SMD: -0.41; 95% CI: -0.75 to -0.08; P =.014). Trials based on the self-reported, clinician-rated or task-based outcomes showed significant heterogeneity across the trials. Trials based on informant-reported outcomes showed substantial heterogeneity across the trials.
Data regarding the effect of CBT on symptoms of social-emotional problems based on self-reported outcomes (9 trials) showed no significant difference between CBT and control groups (SMD: -0.42; 95% CI: -0.90 to 0.07; P =.093). The effect of CBT on symptoms of social-emotional problems based on informant reported outcomes (19 trials) indicated lower symptoms in the CBT group (SMD: -0.71; 95% CI: -1.04 to -0.38; P < .001). Based on clinician-rated outcomes (9 trials) the patients in CBT group showed a significant improvement (SMD: 1.02; 95% CI: 0.58 to 1.46; P < .001). All the trials showed significant heterogeneity across the trials.
Risk of bias: Researchers assessed study quality for each trial by using the JADAD scale which is based on randomization, blinding, allocation concealment, withdrawals and dropouts, and the use of an intention-to-treat analysis. JADAD scores range from 0 to 5 (5 indicating highest quality). In this study, 24 trials scored 4, 16 trials scored 3, 6 trials scored 2, and the remaining 5 trials scored 1. The quality of included studies was assessed to be low to modest and the conclusions of this meta-analysis might be restricted by uncontrolled biases. The outcomes were investigated by various measurements, and this could have affected the net effect estimates. There was significant heterogeneity for all investigated outcomes which may be due to the various CBT strategies and targets across trials. There was no significant publication bias for most of the trials.
For this meta-analysis publication bias was inevitable because the current study was based on published RCTs, and unpublished data were not available. In this meta-analysis there was no information about comparison interventions or the cognitive level of participants.