Changes to a serial resource may be Major or Minor. Major Changes usually require a new description for the resource. Minor changes will not require a new description but will necessitate revising the existing description in some way in most situations.
What constitutes a Major Change has been established by RDA and adopted by CONSER.
Changes to the following elements or areas may constitute a major change depending on the situation.
The title proper
Authorized Access Point representing a corporate body when used in conjunction with the Preferred Title representing a work to construct an authorized access point ($130 qualifier).
Corporate body when used as an addition to the authorized access point representing a work
Preferred Title for different language expressions
Edition statement
Mode of issuance (RDA 1.6.2.1
How Changes are Detected
There are a number of ways in which changes may be discovered. When a cataloger is creating a description with a run of a serial in hand, the change may be detected from looking at the pieces in hand, or a related description may be found that suggests a change.
In other cases, changes will be found by staff checking in the serial. For online resources, the change may be noticed first by a patron or reference librarian. Once the change is detected, the cataloger must then decide whether it is major or minor (CCM:16.2.2).
Occasionally, catalogers receive information from publishers about important forthcoming changes, for example, changes in publisher or issuing body. The MARC 21 588 field is used to record this type of information in advance of the change.