USEFULNESS OF PATIENT INTERVIEW IN BLEEDING DISORDERS

Background: It is not known which questions ina medical interview are most informative for diagnosing mild bleeding disorders, and what the value is of the entire interview in screening for hemostatic disorders. Methods: A questionnaire was sent to 222 patients with a proven bleeding disorder, to 134 patients suspected of a bleeding disorder but whose hemostasis proved normal, and to 341 healthy volunteers. A first comparison, between patients with a bleeding disorder and patients with bleeding complaints whose hemostasis proved normal, mimics the situation in a department of hematology where patients are referred because of complaints. The second comparison, between patients with a proven bleeding disorder and healthy volunteers, may serve as a model for the situation where the interview is used as a screening tool to detect patients with a bleeding disorder in a population where there is no prior suspicion, eg, before surgical intervention. For each question we calculated a univariate odds ratio, multivariate odds ratios, and a positive and negative likelihood ratio. With a receiver operating characteristic curve analysis we evaluated the value of a simple vs an elaborate interview. Results: Ninety-two percent of the questionnaires were returned. For both comparisons the most informative questions were questions about bleeding disorders in the family and traumatic events, with the exception of delivery. Noninformative questions were frequent gum-bleeds and blood in the urine. A receiver operating characteristic curve analysis revealed that a simple interview has a high discriminating power in a screening situation, whereas in a referred situation even an elaborate interview has a low performance. Conclusions: A simple interview is useful as a screening tool for the dentist or surgeon. In a specialized hematology center with referred patients, however, the interview is of little value in identifying patients with a bleeding disorder.