Evaluation of a diagnostic questionnaire for nasal polyposis: an observational, cross-sectional study.

Nasal polyposis (NP) represents actually a matter of concern for most ear, nose and throat (ENT) specialists. In France, we lack data on NP prevalence due to the unavailability of a validated diagnostic questionnaire easily usable in population-based studies. The present study tested the sensitivity and specificity of an 11-item questionnaire for NP diagnosis from which an algorithm of diagnosis decision was inferred. Outpatients from 3 ENT departments were asked to complete the questionnaire prior to their visit. After the visit, the investigator had to write his final diagnosis (FD) on the envelope containing the questionnaire, without reading the patient's responses. Data from 406 patients showed a good specificity and sensitivity of most items. Awareness of NP, previous cortisone therapy for nasal pathology, and history of nasal surgery were shown to be the most discriminating items. An algorithm was elaborated by aggregation of the different items; its specificity and sensitivity were close to 90%. These diagnostic questionnaire and algorithm, although not substitutable to a clinical diagnosis, should be very useful for population-based studies.