text:           Combination of Bernouilli effect producing maneuver-induced pharyngeal narrowing rate with body mass index as predictive tool for obstructive sleep apnea syndrome.  Conclusions. It is suggested that the combination of the pharyngeal narrowing rate during the Bernouilli effect producing maneuver (BEPM) with the body mass index (BMI) might be a promising predictive method for obstructive sleep apnea syndrome (OSAS). Objectives. An attempt was made to clarify the possibility that the dynamic narrowing of the pharynx evaluated by nasopharyngoscopy with BEPM, a forced inspiration through the nose with the mouth closed, might be a reliable clinical daytime predictor for identifying patients at risk of developing OSAS. Subjects and methods. Subjects were 57 patients complaining of snoring and sleepiness during daytime. Endoscopic images of the retropalatal pharynx were obtained and their area was measured by NIH imaging. The pharyngeal narrowing rate during quiet nasal breathing and that during BEPM were compared to assess pharyngeal dynamics. To increase the sensitivity of this method, BMI was added to the pharyngeal narrowing rate during BEPM. Results. The criterion of BEPM at a cut-off value of     with BMI at a cut-off value of 25 kg/m(2) achieved a sensitivity of 93%, while the specificity was 67% in differentiating simple snorers from OSAS patients (apnea index >5). In addition, the likelihood ratio of the method was found to be 2.81.