Diagnostic accuracy of FEV1/forced vital capacity ratio z scores in asthmatic patients.

ABSTRACT:

Background

The FEV1/forced vital capacity (FVC) ratio is used as a criterion for airflow obstruction; however, the test characteristics of spirometry in the diagnosis of asthma are not well established. The accuracy of a test depends on the pretest probability of disease.

Objective

We wanted to estimate the FEV1/FVC ratio z score threshold with optimal accuracy for the diagnosis of asthma for different pretest probabilities.

Methods

Asthmatic patients enrolled in 4 trials from the Asthma Clinical Research Centers were included in this analysis. Measured and predicted FEV1/FVC ratios were obtained, with calculation of z scores for each participant. Across a range of asthma prevalences and z score thresholds, the overall diagnostic accuracy was calculated.

Results

SUBMITTER: Lambert A 

PROVIDER: S-EPMC4562860 | biostudies-literature | 2015 Sep

REPOSITORIES: biostudies-literature