In addition to the wording in the job reference there are other hidden hints. These usually refer to a specific misconduct or character trait that a later employer should be warned of by codes in the employer's reference. As these examples will show, caution is always called for with ambiguous statements – and it might be that these are masking a criticism. This is not always the case, but it is good to double check the context when reading a statement you don’t know what to make of, or are considering how to write the job reference you’ve been asked for.
It should be noted, however, that a job reference must not contain any features or wording intended to convey a hidden message about the employee. Topics that should never be included in a job reference are warnings, alcohol consumption, unemployment, disabilities, works union membership, as well as time off, illness, parental leave, and private information.