The effectiveness of a multidimensional intervention (transcranial direct current stimulation and skill-based cognitive-behavioral intervention) on response inhibition and attentional bias to threat in children with oppositional defiant disorder

To determine the effectiveness of a multidimensional intervention including non-invasive brain electrical stimulation (tDCS) and cognitive-behavioral skill-based intervention (CBT) on response inhibition and attention bias to threat in children with oppositional defiant disorder (ODD).

This study employed a quasi-experimental pretest-posttest design with a control group. Participants were randomly assigned to three groups (two experimental and one control).

The study was conducted in psychological clinics and counseling centers in Tehran. All interventions and assessments were implemented by the researcher under the supervision of the academic advisor.

Inclusion Criteria: Clinical diagnosis of Oppositional Defiant Disorder (ODD) based on DSM-5 by a psychologist or psychiatrist Written informed consent from parents Ability to participate in therapy sessions and computer-based tasks Absence of severe comorbid disorders such as autism spectrum disorder or intellectual disability Exclusion Criteria: Absence from more than two therapy sessions Lack of cooperation during tests or exercises Emergence of new psychological symptoms requiring independent intervention Withdrawal from participation by the child or parents

Experimental Group 1: Received transcranial Direct Current Stimulation (tDCS) for nine 20-minute sessions over three weeks. Experimental Group 2: Received cognitive-behavioral skill-based intervention (CBT) in nine 70-minute weekly sessions. Control Group: Did not receive any intervention during the study period.

Response Inhibition: Scores obtained from the Stroop test (number of errors, correct responses, and reaction time). Attention Bias to Threat: Scores obtained from the Dot-Probe Task.

Randomization method: Simple randomization Unit of randomization: Individual Randomization tool: SPSS software (random number generation) Sequence generation: Participants allocated equally across groups based on random numbers generated Block/stratified randomization: Not applied (small sample, homogeneous population)

Since the individual participant data are confidential and specific to a master’s thesis, public sharing is not recommended.

The individual participant data of this study are confidential and will be used only for scientific analysis within the framework of a master’s thesis. No individual data will be publicly shared; however, the summarized results will be published as a scientific paper.

The study data will be archived for five years after the completion of statistical analysis and thesis defense. Access will be granted only upon formal request by the university or the ethics committee.

Only the principal investigator, the academic supervisor, and, if required, the Ethics Committee of Islamic Azad University of Medical Sciences, Tehran Branch, will have access to the data.

The data may only be used for research purposes within the university’s approved framework. Any secondary use requires formal approval from the university’s Ethics Committee.

Requests should be addressed to the principal investigator (Ms. Elnaz Nazer) through the Faculty of Medicine, Islamic Azad University of Medical Sciences, Tehran.

Requests will be reviewed, and upon approval by the supervisor and the Ethics Committee, anonymized and summarized data may be provided to the applicant if necessary.

The collected data are solely intended for academic and educational purposes of the thesis. Public dissemination of raw data would conflict with the confidentiality principles of participants.