Dimensional assessment of hypochondriacal fears and beliefs.

Background: The hypochondriacal spectrum includes several clinical phenomena, such as disease phobia, thanatophobia and health anxiety. The major challenge for a dimensional tool is to capture the different features which sensitively differentiate the hypochondriacal syndrome from other clinical phenomena, such as somatization. This article provides a qualitative review of the instruments designed for the dimensional assessment of hypochondriacal fears and beliefs. Methods: Articles were retrieved by means of both computerized (Medline, PsycINFO) and manual searches. Results: In the 1960s, the Whiteley Index (WI) was the first instrument specifically built to measure the severity of hypochondriacal symptoms. In the 1980s, Kellner developed the nine Illness Attitude Scales (IAS), each of them concerns a specific cluster of attitudes, fears and beliefs. They were designed to reflect the clinimetric properties, in particular content validity and sensitivity to treatment-related changes. In the 1990s, the refinement of the cognitive-behavioral model of hypochondriasis was followed by an upsurge of questionnaires aimed at assessing the dimensions of hypochondriasis according to this model. However, most of these instruments need to be further validated and the amount of incremental information they yield remains to be established. In the last decade, the interest of the studies has been focused on the measurement of specific features of hypochondriasis, such as response to medical reassurance and obsessive-compulsive symptoms. Conclusions: Kellner’s IAS and Pilowsky’s WI are the most validated and widely used instruments. The clinimetric properties make the IAS the gold standard for the dimensional assessment of hypochondriacal fears and beliefs.