RESUMO
BACKGROUND: Medically unexplained symptoms are difficult to measure and in most cases the diagnosis is made either from independent data such as consultants' opinions or medical outcomes, or by proxy measures such as numbers of symptoms or consultations. A valid self-rated measure would be of value in assessing this highly prevalent condition. AIMS: To describe a new scale of nine items, the Schedule for Evaluation of Persistent Symptoms (SEPS), its properties, its internal consistency, its distribution in a sample of 470 medical patients, its relationship to social functioning and health anxiety (hypochondriasis), and its construct validity by comparing its results with an independent diagnostic examination of each patient's notes two years subsequent to assessment. METHOD: A prevalence study was carried out in 405 consenting medical patients in primary care, cardiology, respiratory medicine, gastroenterology and endocrine clinics, in which the SEPS scale, the Health Anxiety Inventory (HAI) and the Social Functioning Questionnaire (SFQ) were each completed. RESULTS: The mean score on the SEPS scale in 470 patients was 13.4. Exploratory factor analysis revealed two main factors, one concerned focus on symptoms and the other on their attribution. Examination of all data showed a cut-off point of 14 as indicating the presence of pathological medically unexplained symptoms (MUS). Agreement between the consultants' diagnosis and pathological MUS scores was fairly good with a score of 14 or more on the SEPS showing sensitivity of 0.65 and negative predictive accuracy of 0.90. CONCLUSION: It is concluded that the SEPS scale has potential value in screening patients with suspected medically unexplained symptoms.