What works for whom in pediatric OCD: description of causally interpretable meta-analysis methods and report on trial...

Area of Science:

• Clinical Epidemiology
• Biostatistics
• Pediatric Psychiatry

Background:

• Understanding treatment efficacy for specific patient subgroups (
• what works, for whom?
• ) is crucial for improving patient outcomes in pediatric obsessive-compulsive disorder (OCD).
• Individual clinical trials often lack the statistical power to address these nuanced questions.
• Existing meta-analysis methods struggle to account for heterogeneity across trials, limiting causal inference.

Purpose of the Study:

• To describe the methods and progress of a large-scale data harmonization project for pediatric OCD.
• To apply causally interpretable meta-analysis (CI-MA) to individual-participant data (IPD) from multiple randomized controlled trials (RCTs).
• To extend causal inferences to target clinical populations of youth with OCD.

Main Methods:

• Harmonization of individual-participant data (IPD) from 28 randomized controlled trials (RCTs) in pediatric OCD.
• Acquisition and harmonization of target data from a clinical sample of treatment-seeking youth (ages 4-20) with OCD.
• Application of causally interpretable meta-analysis (CI-MA) techniques to the harmonized IPD.

Main Results:

• Project Harmony successfully harmonized IPD from 28 RCTs and acquired target clinical data.
• The data harmonization process required approximately 3,000 hours, exceeding initial projections.
• CI-MA was applied to investigate treatment effectiveness within specific patient profiles in pediatric OCD.

Conclusions:

• Causally interpretable meta-analysis (CI-MA) offers a robust framework for synthesizing IPD across trials.
• Harmonizing data through CI-MA has significant potential to answer critical
• what works, for whom?
• questions in pediatric OCD.
• The findings can enhance the clinical utility and applicability of meta-analysis in child mental health research.