1. DESCRIPTION OF THE DATA FIELD:

Variable length

Optional filling Repetitive

2. DATA ELEMENT DEFINITION:

Keywords suggested by the Author and/or Editor of the document.

3. NOTES:

a) All keywords should be recorded, even if they exist in DeCS/MeSH.

b) Qualifiers, if any, should be recorded in the attribute s: qualifier;

c) The language should be selected according to ISO 639:1988 standard in the attribute i: Language;

d) Authors are advised to use DeCS/MeSH in choosing keywords. If there are no DeCS/MeSH descriptors to cover the document’s theme, terms or expressions commonly used in the area may be indicated.

4. EXAMPLES:

a) Perimetry s:instrumentation i:pt

b) Perimetry s:instrumentation i:en Aging i:pt

c) Case Reports [Publication Type] i:pt d) Rats i:pt