custom-type Custom Attribute Value Escape Hatch

Used in the same attribute list as an attribute with a set list of values, to provide a way for the content creator to say “my attribute value is not on the set list”.

Usage/Remarks

For use only in the same attribute list as an attribute whose value comes from a set list.
This attribute would be unnecessary in BITS if BITS were not part of the JATS ecosystem. The situation this attribute was developed for does not occur in BITS. However, it does occur in JATS, and because many BITS documents are created from JATS documents, this is allowed in BITS to accommodate import from JATS.
Custom Value
When a JATS tagger needs to record an attribute value that is not named on the list of possible attribute values, they use the value “custom”. This tells a JATS processor that this attribute value is not one of the named values. BITS, which has almost no attribute value lists, has defined this attribute for the sake of JATS, so that JATS articles bodies can become BITS book parts with as few changes as possible.
The Best JATS Practice (unenforceable in DTDs, but very enforceable in Schematron, for example) is, that if you use the value “custom” for an attribute, you should then record what type of custom (the value not in the set list) in the @custom-type attribute. For example:
<person-group @person-group-type=”custom” custom-type=”statisticians”>
<xref @ref-type=”custom” custom-type=”data-avail-statement”>
OPTIONAL on many elements; click for list and usage
Value Meaning
The value of the type attribute for the element to which this attribute is attached. Used only when the value is not found in a set list of values. The @custom-type is used in versions of JATS that have a static list of values for some attribute, for example, for the @fn-type attribute. To add a value to such a list, the @fn-type attribute is given the type “custom” and a separate @custom-type attribute provides the typing value. There is no need for such a typing mechanism in BITS, since there are no restrictions on the value of the attributes that share an attribute list with @custom-type. Nevertheless, the value “custom” and the attribute @custom-type have both been included in BITS so that articles valid to a stricter version of the JATS Tag Set will also be valid as book-parts in BITS.
Restriction @custom-type is an optional attribute; there is no default.