Abstract
In Scandinavia, phoniatrists deal with all kinds of disorders of oral communication. Oral communication is behaviour. From a medical point of view, disturbances in a person's speech, voice and language behaviour are symptoms. Thus, phoniatric diagnosis primarily involves analysis and classification of symptoms. Secondly, but medically more important, the phoniatrist must find out what causes the symptoms and deviant behaviour, and arrive at an aetiological diagnosis. A number of problems pertain to phoniatric diagnosis, such as definitions of normalcy, measuring procedures to determine degrees of abnormalcy, and terminology.