Variability in interpretation of chest radiographs among Russian clinicians and implications for screening programmes: observational study.

OBJECTIVE To determine variability in interpretation of chest radiographs among tuberculosis specialists, radiologists, and respiratory specialists. DESIGN Observational study. SETTING Tuberculosis and respiratory disease services, Samara region, Russian Federation. PARTICIPANTS 101 clinicians involved in the diagnosis and management of pulmonary tuberculosis and respiratory diseases. MAIN OUTCOME MEASURES Interobserver and intraobserver agreement on the interpretation of 50 digital chest radiographs, using a scale of poor to very good agreement (kappa coefficient: < or = 0.20 poor, 0.21-0.40 fair, 0.41-0.60 moderate, 0.61-0.80 good, and 0.81-1.00 very good). RESULTS Agreement on the presence or absence of an abnormality was fair only (kappa = 0.380, 95% confidence interval 0.376 to 0.384), moderate for localisation of the abnormality (0.448, 0.444 to 0.452), and fair for a diagnosis of tuberculosis (0.387, 0.382 to 0.391). The highest levels of agreement were among radiologists. Level of experience (years of work in the specialty) influenced agreement on presence of abnormalities and cavities. Levels of intraobserver agreement were fair. CONCLUSIONS Population screening for tuberculosis in Russia may be less than optimal owing to limited agreement on interpretation of chest radiographs, and may have implications for radiological screening programmes in other countries.