The PRISMA dataset is organised according to the Brain Imaging Data Structure 
(BIDS) specification version 1.10.1 and is publicly available at doi:10.18112/openneuro.ds007182.v1.0.0 
under accession number ds007182.

### Planned analysis
This dataset is released at the same time as the data descriptor, before we have published any analysis of it. Collecting it took over 18 months of recruitment, testing and quality control. Recruiting and retaining autistic adults for repeated sessions of this length required sustained contact with each participant and adaptations to the testing procedure developed with an expert-by-experience panel. The scanning was paid for by the Netherlands Organisation for Research (NWO) and the acquisition, curation and preprocessing required the work of many people. Datasets of this kind are often embargoed for several years so that the group that did this work has first use of it. We decided against an embargo. Releasing the data now means our own analyses can be checked against them from the start, and it makes the dataset useful to others without delay. That decision does not make the data cost-free, and we ask users to keep the following in mind.

We are working on these analyses ourselves:
- Stability and reliability of functional connectomes in autistic adults 
- Individual variation in functional anatomy in autistic adults 
- Processing of naturalistic video and its relation to spontaneous thought in autism 
- Coupling between white matter structural connectivity and functional dynamics in autism 

If you are planning work on any of these, please contact us first. We would rather coordinate or collaborate than duplicate. This request stands until the corresponding preprints are posted; we will link them here and remove items as they appear.

Last updated: 8 September 2026.

### Key naming conventions:

- Participant labels: sub-001 to sub-066
- Session labels: ses-01, ses-02, ses-03
- Task labels: rest, news, realitytv
- Run labels: run-01, run-02, run-03, ...
- Direction labels (dwi/fmap): AP (anterior-posterior), PA (posterior-anterior)

### File Formats

All neuroimaging data are stored as compressed NIfTI files (.nii.gz) with 
accompanying JSON sidecar files containing acquisition parameters. Physiological 
recordings are stored as compressed tab-separated value files (.tsv.gz) following 
BIDS specification for physiological recordings. Behavioural and phenotypic data 
are provided as tab-separated value files (.tsv) with JSON metadata files.

### Metadata Files

- `dataset_description.json`: Dataset-level metadata including BIDS version, 
  dataset name, authors, and acknowledgements
- `participants.tsv`: Demographic information for all participants (age, sex, 
  handedness, group assignment, education level, time between sessions)
- `participants.json`: Data dictionary for participants.tsv
- `README`: Detailed dataset description, experimental procedures, and data 
  collection protocols
- `CHANGES`: Version history and dataset updates
- `*_scans.tsv`: Scan-specific metadata (acquisition time, quality notes)


### Derivatives

Preprocessed data are provided in `derivatives/` following BIDS Derivatives 
specification:

- `fmriprep/`: Functional MRI data preprocessed with fMRIPrep version 25.2.3, including motion-corrected, spatially normalised, and surface-projected data
- `qsiprep/`: Diffusion MRI data preprocessed with QSIPrep version 1.0.2,  including denoised, distortion-corrected, and eddy-current-corrected data
- `qsirecon/`: Structural connectomes derived using mrtrix_singleshell_ss3t  pipeline with anatomically constrained tractography
- `physio/`: Physiological data for peak detection, heart rate  variability, and respiratory volume per time calculations

Each derivative directory contains a `dataset_description.json` file specifying 
the generating software and version.

### Defacing and Privacy

All structural images have been defaced using MiDeFace 2, which is part of 
FreeSurfer v7.4.1 Docker image. The de-facing mask was derived using the 
T1-weighted images and applied to the T2-weighted images after corregistration 
using the ‘mri_coreg’ function of FreeSurfer.  


### Missing Data

Not all participants have complete data across all modalities and sessions. 
Data availability is documented in:
- `participants.tsv`: Indicates which sessions each participant completed
- `sub-<label>_sessions.tsv`: Session-specific completion status
- Individual `*_scans.tsv` files: Scan-level quality notes and usability flags

Known missing data patterns:
- T1w images: 65/65 participants (100%)
- T2w images: 62/65 participants (95.4%)
- DWI: 61/65 participants (94.8%)
- Functional scans: See Scientific Data publication for detailed breakdown
- Physiological recordings: See Scientific Data publication for detailed breakdown

### Data Access and Licensing

The dataset is available on OpenNeuro under Creative Commons CC0. Users must cite this data 
descriptor publication when using the dataset.

- DOI: 10.18112/openneuro.ds007182.v1.0.0
- Repository: https://openneuro.org/datasets/ds007182
- Accession number: ds007182

### Data Use Agreement

All participants provided written informed consent for public data sharing. 
Users are required to:
1. Cite this data descriptor in any publications using the dataset
2. Respect participant privacy by not attempting re-identification
3. Follow repository-specific terms of use

Technical Validation data and analysis code are available at [https://github.com/joebathelt/ASDPrecision](https://github.com/joebathelt/ASDPrecision).