@@ -116,13 +116,13 @@ PEP will (look up and) replace the participant's short pseudonym by a placeholde
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@@ -116,13 +116,13 @@ PEP will (look up and) replace the participant's short pseudonym by a placeholde
### Downloading BIDS data
### Downloading BIDS data
BIDS data can be downloaded by means of the `pepcli pull` command without needing to supply additional switches. E.g.:
BIDS data can be downloaded by means of the `pepcli pull` command by just including it in the set of columns, or by specifying a column group containing the column. E.g.:
While data are usually downloaded onto the local file system as a single file, columns configured with BIDS support will produce a directory instead. The directory will be populated with the files that were [originally uploaded](#uploading-bids-data). Within those files, however, any values originally containing the MRI data's short pseudonym will have been replaced by the [user pseudonym](Pseudonymization#identifiers-in-pep) for that participant. This user pseudonym can then be used as a identifier for the subject and/or MRI data during further processing. It should be noted that
While data are usually downloaded onto the local file system as a single file, columns configured with BIDS support will produce a *directory* instead. The directory will be named after the column (e.g. `Visit1.MRI.Anat` in the example) and filled with the files that were [originally uploaded](#uploading-bids-data). Within those files, however, any values originally containing the MRI data's short pseudonym will have been replaced by the [user pseudonym](Pseudonymization#identifiers-in-pep) for that participant. This user pseudonym can then be used as a identifier for the subject and/or MRI data during further processing. It should be noted that
- a substring of the user pseudonym will be used if the original short pseudonym was shorter.
- a substring of the user pseudonym will be used if the original short pseudonym was shorter.
- if downloaders wish to join MRI data for multiple subjects into a single BIDS data set, they must (use third-party tooling to) do so themselves.
- if downloaders wish to join MRI data for multiple subjects into a single BIDS data set, they must (use third-party tooling to) do so themselves.