diff --git a/src/02-common-principles.md b/src/02-common-principles.md index 0736457e1c..8280542646 100644 --- a/src/02-common-principles.md +++ b/src/02-common-principles.md @@ -661,6 +661,20 @@ it refers to. For example `sub-01` refers to the `sub` entity (a subject) with the label `01`. The `sub-` prefix is not part of the subject label, but must be included in filenames (similarly to other key names). +## Specification of paths + +Several metadata fields in BIDS require the specification of paths, +that is, a string of characters used to uniquely identify a location in a directory structure. +For example the `IntendedFor` or `AssociatedEmptyroom` metadata fields. + +Throughout BIDS all such paths MUST be specified using the slash character (`/`), +regardless of the operating system that a particular dataset is curated on or used on. + +Paths SHOULD NOT be absolute local paths, +because these might break when a dataset is used on a different machine. +It is RECOMMENDED that all paths specified in a BIDS dataset are relative paths, +as specified in the respective descriptions of metadata fields that require the use of paths. + ## Uniform Resource Indicator A Uniform Resource Indicator (URI) is a string referring to a resource and SHOULD