"Dictated But Not Read" is a phrase used at the end of a text to warn that the written material has not been personally written or verified by the author

Author

An author is broadly defined as "the person who originates or gives existence to anything" and that authorship determines responsibility for what is created. Narrowly defined, an author is the originator of any written work.-Legal significance:...

. The material may have been dictated

Dictation

Dictation can refer to:*Dictation , when one person speaks while another person transcribes what is spoken.*A dictation machine, a device used to record speech for transcription....

 to a secretary

Secretary

A secretary, or administrative assistant, is a person whose work consists of supporting management, including executives, using a variety of project management, communication & organizational skills. These functions may be entirely carried out to assist one other employee or may be for the benefit...

when the author had no time to proofread or edit it.

This practice is more common within the medical community, though its appropriateness is still debated.