Eligibility criteria

Studies included in the ReFiNe Replication Hub are identified through systematic literature searches and screened using predefined eligibility criteria. Candidate studies first undergo an eligibility assessment and are subsequently evaluated regarding their suitability for direct replication using available datasets.

Scientific scope of ReFiNe

ReFiNe is designed to support systematic direct replications within the clinical domains described below (based on available ENIGMA working groups) and for a selection of voxel-based MRI modalities.

Clinical domains

• Affective disorders (depression and bipolar disorder)
• Anxiety disorders (including PTSD and OCD)
• Psychotic disorders
• Neurodevelopmental disorders (ADHD and ASD)
• Addiction
• Epilepsy
• Parkinson’s disease
• Stroke
• Ataxia

MRI modalities

• Voxel-based morphometry (VBM)
• Resting-state functional MRI
• Task-based functional MRI

General eligibility criteria

Eligible studies must:

• report an original MRI finding associating a predictor with brain structure or function;
• investigate predictors related to mental health or neurological disorders (e.g., diagnosis, symptoms, treatment response, disease progression, risk or protective factors, or disorder-related biomarkers);
• include human participants from clinical and/or non-clinical populations (neonatal or infant-specific MRI methodologies are excluded);
• use voxel-wise gray matter structure (VBM) or voxel-wise functional findings (task-based or resting-state fMRI), based on cerebral MRI scans acquired at a minimum field strength of 3 T, with isotropic voxels and a spatial resolution of at least 1.5 mm for VBM (3.5 mm for fMRI);
• use whole-brain, mass-univariate voxel-based MRI analyses within a general linear modelling framework or a comparable statistical approach (multivariate machine-learning approaches are excluded);
• be published as primary research articles in peer-reviewed journals and be available in English.

Replication-specific feasibility assessment

For each selected replication target, the replication team evaluates whether direct replication is feasible using the available dataset. This assessment includes:

• availability of a comparable predictor variable;
• availability of required covariates;
• sufficiently similar sample characteristics;
• comparable MRI modality and statistical analysis;
• comparable study design (e.g., cross-sectional or longitudinal);
• a replication sample size at least as large as the original study.

Only studies meeting these feasibility criteria are approved for direct replication.