Validation of nasal pressure for the identification of XXXX .

@entity1 @entity387 @entity27 @entity1576 @entity386
The reference standard for identifying @entity386 and @entity387 is a pneumotachograph, but using this can disrupt sleep. Nasal airflow estimation by measuring nasal pressure via nasal prongs is better tolerated by @entity1 . However, nasal pressure has not been validated, using an event-by-event analysis, for detecting @entity27 . Eleven @entity1 undergoing polysomnography wore a nasal mask capable of measuring nasal airflow (via pneumotachograph) and nasal pressure simultaneously. Each study was screened for @entity1576 , and from these 550 were randomly selected and blindly scored as an @entity386 / @entity387 or no event each using the pneumotachograph, nasal pressure, square root nasal pressure, and respiratory inductance sum signals independently. Agreement was measured using Cohen's kappa statistic. Intermeasurement agreements between the pneumotachograph and nasal pressure, square root nasal pressure, and respiratory inductance plethysmography sum were 0.76, 0.73, and 0.50, respectively. Inter- and intrarater agreements were, respectively, 0.68 and 0.60 for the pneumotachograph, 0.66 and 0.82 for nasal pressure, 0.61 and 0.78 for square root nasal pressure, and 0.47 and 0.76 for respiratory inductance plethysmography sum. These results indicate that nasal pressure has excellent agreement compared with a pneumotachograph and very good inter-/intrarater agreement. Square root transformation of the nasal pressure signal does not improve these levels of agreement, indicating that it is unnecessary in routine clinical practice for scoring @entity386 / @entity387 .
