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degree-contribution Degree of Contribution

Indicates the level of contribution for this contributor, such as “Lead” or “Supporting”.
OPTIONAL on element: <role>
Value Meaning
Text, numbers, or special characters The degree of contribution, for example, “Lead” or “Equal”.
Restriction @degree-contribution is an optional attribute; there is no default.

Suggested usage

While the values of this attribute are unconstrained, the expected values (particularly useful for CRediT roles) are:
Lead
The contributor was one of the lead contributors.
Supporting
The contributor was one of the supporting contributors, not a lead.
Equal
The contributor was neither a lead nor a supporting contributor; all contributors were equal.
Tagged Sample

Two contributors with level of participation

...
<contrib-group>
 <contrib>
  <string-name><given-names>Barbara</given-names> <surname>Johnston</surname></string-name>
  <role vocab="CRediT" 
    vocab-identifier="http://credit.niso.org/"
    vocab-term="Conceptualization"
    vocab-term-identifier=
    "http://credit.niso.org/contributor-roles/conceptualization/"
    degree-contribution="lead">study designer</role>
 </contrib>
 <contrib>
  <string-name><given-names>Brooke</given-names> <surname>Jackson</surname></string-name>
  <role vocab="CRediT" 
    vocab-identifier="http://credit.niso.org/"
    vocab-term="Writing &#8212; original draft"
    vocab-term-identifier=
    "http://credit.niso.org/contributor-roles/writing-original-draft/"
    degree-contribution="lead">writer</role>
 </contrib>
</contrib-group>
...