The diagnostic and prognostic significance of the Whitely Index, the Illness Attitude Scales and the Somatosensory Amplification Scale.

Abstract

The aim of this study was to assess the ability of the Whitely Index, Illness Attitude Scales and Somatosensory Amplification Scale to differentiate in patients with medically unexplained physical symptoms between hypochondriacal and non-hypochondriacal patients and to examine whether the scores on these questionnaires are predictive of long-term outcome in terms of recovery of presenting symptoms and number of visits to the general practitioner. The study population consisted of 183 consecutive patients, who presented with medically unexplained physical symptoms to a general medical out-patient clinic. The Health Anxiety subscale of the Illness Attitude Scales and the Whitely Index were best in discriminating between hypochondriacal and non-hypochondriacal patients. The sensitivity and specificity of the Health Anxiety subscale of the Illness Attitude Scales were 79% and 84%, and of the Whitely Index 87% and 72%. The Whitely Index was negatively associated with recovery rate at 1 year follow-up. The Illness Behaviour subscale of the Illness Attitude Scales appeared to be predictive of the number of visits to the general practitioner. These findings might have clinical implications in helping to distinguish in patients with medically unexplained symptoms those for whom there is a high chance of persistence of the symptoms and/or of high medical care utilization.