Meta-Analytic Psychotherapy Research,

Open for Everyone.

Tools & Features of the Metapsy Project


A Unified Framework of Meta-Analytic Databases

Metapsy implements the concept of a “meta-analytic research domain” (MARD) for psychological interventions. We provide access to “living” databases that cover an entire research field, and are therefore broader than what can be covered by a single systematic review.

Our goal is to provide up-to-date data on the effects psychotherapy compared to various control groups and alternative treatments, and across all major mental disorders.


Documentation, Versioning & Indexing

All meta-analytic databases included in Metapsy are provided with rich metadata, in which the study search, extraction and coding steps are detailed. We also provide a detailed documentation for each database to increase transparency. All databases are versioned and archived on a public research data repository.

A Digital Object Identifier (DOI) is provided for all versions of each database, which can be used to unambiguously reference each database (and its specific version).


Meta-Analytic Synthesis

Simplified versions of all databases can be explored using the online meta-analysis tool included in Metapsy. This tool allows to select clinical trial data of interest, analyze overall effects in real-time using state-of-the-art meta-analysis methods, and explore effect heterogeneity using subgroup tests and meta-regression models.

An improved version of the online meta-analysis tool is currently under construction and will be released soon.


R Packages

Metapsy includes two R packages to simplify the use of the provided data for researchers. The metapsyData package can be used to download all databases (and versions thereof) directly into an R environment. All data is provided in a standardised format, and codebooks are provided in the documentation. Using metapsyTools, all databases can be analyzed “out of the box” using state-of-the-art statistical methods. To export all databases and metadata in a machine-readable format, the Metapsy API can be used.

This website is intended for healthcare professionals.