Survey of physicians' approaches to the clinical evaluation of interstitial lung disease in Singapore (SoPhoCLES).

Background: The diagnostic gold standard for interstitial lung disease (ILD) has evolved from histopathology to multidisciplinary discussion (MDD) consensus. However, physicians' practices remain heterogeneous, impacting upon core data acquisition, interpretation and eventual MDD diagnosis. Our study compared approaches between ILD (fellowship-trained and providing dedicated ILD services) and non-ILD physicians in Singapore. Methods: Between October 2017 and January 2018, non-ILD respiratory physicians from public hospitals in Singapore were invited to participate in a survey designed by a focus group comprising ILD and non-ILD physicians. Responses of local ILD physicians were benchmarked against that of overseas ILD physicians from expert centres and thoracic radiologists. Results: Fifty-nine of ninety-six (61%) local physicians responded. As practices between local and overseas ILD physicians revealed no significant differences, they were pooled together for analysis. ILD physicians diagnosed more cases annually, presented more frequently at MDD, utilised supportive tests more consistently, reported higher confidence levels interpreting high resolution computed tomography (HRCT) and placed higher weightage on physician rather than radiologist or pathologist opinion. In four case-based scenarios, there were higher levels of agreement in diagnoses among ILD than non-ILD physicians. Inter-rater agreement on radiological diagnoses was moderate among ILD physicians (κ=0.55) and between ILD physicians and radiologists (κ=0.56), but fair among non-ILD physicians (κ=0.29) and both physician groups (κ=0.25). Inter-rater agreement on clinical diagnoses was moderate among ILD physicians (κ=0.52), but fair among non-ILD physicians (κ=0.35). Conclusions: Substantial differences between ILD physicians and non-ILD physicians exist. Early referral to appropriate expertise is recommended.