Interobserver Variability in Applying a Radiographic Definition for ARDS: Discussion
This wide range in the percentage of radiograph readers termed positive was not due to isolated outliers, but reflected a continuous distribution across all readers (Table 2). These data provide empiric evidence for the concerns that have been raised regarding the reproducibility of the ALI-ARDS definition for different institutions. If the variability in radiographic interpretation causes variability in the clinical diagnosis of ALI-ARDS, this finding may account for some of the geographic and institutional variation in the incidence, risk factors, resource use, and outcome of ALI-ARDS. natural asthma inhaler
Only one other published study has evaluated interobserver variability in ARDS chest radio-graphs. These investigators found excellent agreement between two radiologists and poor agreement between four nonradiologist clinicians in calculating a radiographic score in a series of chest radiographs from patients who had ARDS diagnoses. Ours is the first study to explore the reliability of an accepted consensus conference radiographic definition (as opposed to a scoring system) in a set of chest radiographs. In addition, the radiographs in our study were selected only on the basis of intubation and hypoxemia, therefore representing a broad range of radiographs, unlike the earlier study, in which radiographs were selected from patients who had already received diagnoses of ARDS. An additional strength of our study was the group of 21 international experts in ALI-ARDS and mechanical ventilation who were the participating readers. The previous study used readers from a single institution who interpreted the radiographs together. Our study sample may be more representative of interobserver variability. Finally, we report feedback from the readers on specific aspects of the radiographs that led to variability in interpretation; definitions can be modified based on these findings.