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Appendix IV: Entity table

This section compiles the entities (key-value pairs) described throughout this specification, and establishes a common order within a filename. For example, if a file has an acquisition and reconstruction label, the acquisition entity must precede the reconstruction entity. REQUIRED and OPTIONAL entities for a given file type are denoted; empty cells imply that entities MUST NOT be specified. Entity formats indicate whether the value is alphanumeric (<label>) or numeric (<index>).

A general introduction to entities is given in the section on filename structure, while entity definitions are in Appendix IX.

Magnetic Resonance Imaging

Entity Subject Session Task Acquisition Contrast Enhancing Agent Reconstruction Phase-Encoding Direction Run Corresponding Modality Echo Flip Angle Inversion Time Magnetization Transfer Part Recording
Format sub-<label> ses-<label> task-<label> acq-<label> ce-<label> rec-<label> dir-<label> run-<index> mod-<label> echo-<index> flip-<index> inv-<index> mt-<label> part-<label> recording-<label>
anat
(T1w T2w PDw T2starw FLAIR inplaneT1 inplaneT2 PDT2 angio T2star FLASH PD)
REQUIRED OPTIONAL OPTIONAL OPTIONAL OPTIONAL OPTIONAL OPTIONAL
anat
(T1map T2map T2starmap R1map R2map R2starmap PDmap MTRmap MTsat UNIT1 T1rho MWFmap MTVmap PDT2map Chimap S0map M0map)
REQUIRED OPTIONAL OPTIONAL OPTIONAL OPTIONAL OPTIONAL
anat
(defacemask)
REQUIRED OPTIONAL OPTIONAL OPTIONAL OPTIONAL OPTIONAL OPTIONAL
anat
(MESE MEGRE)
REQUIRED OPTIONAL OPTIONAL OPTIONAL OPTIONAL OPTIONAL REQUIRED OPTIONAL
anat
(VFA)
REQUIRED OPTIONAL OPTIONAL OPTIONAL OPTIONAL OPTIONAL OPTIONAL REQUIRED OPTIONAL
anat
(IRT1)
REQUIRED OPTIONAL OPTIONAL OPTIONAL OPTIONAL OPTIONAL REQUIRED OPTIONAL
anat
(MP2RAGE)
REQUIRED OPTIONAL OPTIONAL OPTIONAL OPTIONAL OPTIONAL OPTIONAL OPTIONAL REQUIRED OPTIONAL
anat
(MPM MTS)
REQUIRED OPTIONAL OPTIONAL OPTIONAL OPTIONAL OPTIONAL OPTIONAL REQUIRED REQUIRED OPTIONAL
anat
(MTR)
REQUIRED OPTIONAL OPTIONAL OPTIONAL OPTIONAL OPTIONAL REQUIRED OPTIONAL
dwi
(dwi sbref)
REQUIRED OPTIONAL OPTIONAL OPTIONAL OPTIONAL OPTIONAL OPTIONAL
dwi
(physio stim)
REQUIRED OPTIONAL OPTIONAL OPTIONAL OPTIONAL OPTIONAL OPTIONAL OPTIONAL
fmap
(phasediff phase1 phase2 magnitude1 magnitude2 magnitude fieldmap)
REQUIRED OPTIONAL OPTIONAL OPTIONAL
fmap
(epi m0scan)
REQUIRED OPTIONAL OPTIONAL OPTIONAL REQUIRED OPTIONAL
fmap
(TB1DAM)
REQUIRED OPTIONAL OPTIONAL OPTIONAL OPTIONAL OPTIONAL REQUIRED OPTIONAL OPTIONAL
fmap
(TB1EPI)
REQUIRED OPTIONAL OPTIONAL OPTIONAL OPTIONAL OPTIONAL REQUIRED REQUIRED OPTIONAL OPTIONAL
fmap
(TB1AFI TB1TFL TB1RFM RB1COR)
REQUIRED OPTIONAL OPTIONAL OPTIONAL OPTIONAL OPTIONAL OPTIONAL OPTIONAL OPTIONAL OPTIONAL
fmap
(TB1SRGE)
REQUIRED OPTIONAL OPTIONAL OPTIONAL OPTIONAL OPTIONAL OPTIONAL REQUIRED REQUIRED OPTIONAL
fmap
(TB1map RB1map)
REQUIRED OPTIONAL OPTIONAL OPTIONAL OPTIONAL OPTIONAL
func
(bold cbv sbref)
REQUIRED OPTIONAL REQUIRED OPTIONAL OPTIONAL OPTIONAL OPTIONAL OPTIONAL OPTIONAL OPTIONAL
func
(phase)
REQUIRED OPTIONAL REQUIRED OPTIONAL OPTIONAL OPTIONAL OPTIONAL OPTIONAL OPTIONAL
func
(events)
REQUIRED OPTIONAL REQUIRED OPTIONAL OPTIONAL OPTIONAL OPTIONAL OPTIONAL
func
(physio stim)
REQUIRED OPTIONAL REQUIRED OPTIONAL OPTIONAL OPTIONAL OPTIONAL OPTIONAL OPTIONAL
perf
(asl aslcontext m0scan)
REQUIRED OPTIONAL OPTIONAL OPTIONAL OPTIONAL OPTIONAL
perf
(asllabeling)
REQUIRED OPTIONAL OPTIONAL OPTIONAL OPTIONAL
perf
(physio stim)
REQUIRED OPTIONAL OPTIONAL OPTIONAL OPTIONAL OPTIONAL OPTIONAL

Biopotential Amplification (EEG and iEEG)

Entity Subject Session Task Acquisition Run Space Recording
Format sub-<label> ses-<label> task-<label> acq-<label> run-<index> space-<label> recording-<label>
eeg
(coordsystem electrodes)
REQUIRED OPTIONAL OPTIONAL OPTIONAL
eeg
(channels eeg events)
REQUIRED OPTIONAL REQUIRED OPTIONAL OPTIONAL
eeg
(photo)
REQUIRED OPTIONAL OPTIONAL
eeg
(physio stim)
REQUIRED OPTIONAL REQUIRED OPTIONAL OPTIONAL OPTIONAL
ieeg
(coordsystem electrodes)
REQUIRED OPTIONAL OPTIONAL OPTIONAL
ieeg
(channels events ieeg)
REQUIRED OPTIONAL REQUIRED OPTIONAL OPTIONAL
ieeg
(photo)
REQUIRED OPTIONAL OPTIONAL
ieeg
(physio stim)
REQUIRED OPTIONAL REQUIRED OPTIONAL OPTIONAL OPTIONAL

Magnetoencephalography (MEG)

Entity Subject Session Task Acquisition Run Processed (on device) Space Split Recording
Format sub-<label> ses-<label> task-<label> acq-<label> run-<index> proc-<label> space-<label> split-<index> recording-<label>
meg
(meg)
REQUIRED OPTIONAL REQUIRED OPTIONAL OPTIONAL OPTIONAL OPTIONAL
meg
(meg)
REQUIRED OPTIONAL REQUIRED
meg
(markers)
REQUIRED OPTIONAL OPTIONAL OPTIONAL OPTIONAL
meg
(channels)
REQUIRED OPTIONAL REQUIRED OPTIONAL OPTIONAL OPTIONAL
meg
(events)
REQUIRED OPTIONAL REQUIRED OPTIONAL OPTIONAL
meg
(coordsystem headshape photo)
REQUIRED OPTIONAL OPTIONAL
meg
(physio stim)
REQUIRED OPTIONAL REQUIRED OPTIONAL OPTIONAL OPTIONAL OPTIONAL

Positron Emission Tomography (PET)

Entity Subject Session Task Tracer Reconstruction Run Recording
Format sub-<label> ses-<label> task-<label> trc-<label> rec-<label> run-<index> recording-<label>
pet
(pet)
REQUIRED OPTIONAL OPTIONAL OPTIONAL OPTIONAL OPTIONAL
pet
(blood)
REQUIRED OPTIONAL OPTIONAL OPTIONAL OPTIONAL OPTIONAL REQUIRED
pet
(events)
REQUIRED OPTIONAL REQUIRED OPTIONAL OPTIONAL OPTIONAL
pet
(physio stim)
REQUIRED OPTIONAL OPTIONAL OPTIONAL OPTIONAL OPTIONAL OPTIONAL

Behavioral Data

Entity Subject Session Task Acquisition Run Recording
Format sub-<label> ses-<label> task-<label> acq-<label> run-<index> recording-<label>
beh
(stim physio)
REQUIRED OPTIONAL REQUIRED OPTIONAL OPTIONAL OPTIONAL
beh
(events beh)
REQUIRED OPTIONAL REQUIRED OPTIONAL OPTIONAL

Microscopy

Entity Subject Session Sample Acquisition Stain Run Chunk
Format sub-<label> ses-<label> sample-<label> acq-<label> stain-<label> run-<index> chunk-<index>
micr
(TEM SEM uCT BF DF PC DIC FLUO CONF PLI CARS 2PE MPE SR NLO OCT SPIM)
REQUIRED OPTIONAL REQUIRED OPTIONAL OPTIONAL OPTIONAL OPTIONAL
micr
(photo)
REQUIRED OPTIONAL REQUIRED OPTIONAL