The differential diagnosis of nasal mucosal swelling and adenoidal hyperplasia using two- and three-parameter discriminant functions.

Elevated nasal resistance, as a result of nasal mucosal swelling and/or adenoidal hyperplasia, has been associated with an increased incidence of mouth breathing, which may lead to alterations in facial morphology. The classical approach to studying this problem clinically has been through the adoption of percentiles and various other norms. However, these techniques are only crude estimates and are subject to error. We have developed a novel approach to the assessment of nasal resistance measurements that provides the means for its differential diagnosis. Two- and three-parameter discriminant (or classification) functions were found to replicate an experienced orthodontist's clinical diagnosis very accurately. We also propose the adoption of "sensitivity" and "specificity" when discussing the evaluation and/or success of such models.