Definition reprinted with permission from Hood, Stephen B. (editor) available from Stuttering Foundation of America: [amazon 093338825X inline]
When assessing the overt features of stuttering, it is necessary to consider how often the stutterer engages in various stuttering behaviors, as well as how often he engages in specific behaviors designed to avoid and/or escape from moments of stuttering. (Other overt features include the duration of moments of stuttering, the type of stuttering behaviors and the extent to which these are accompanied by effort, tension and struggle.) In the assessment of stuttering, the mere tabulation of frequency may sometimes be misleading because of the ability of "interiorized stutterers" to avoid and hide the overt features of their disorder.