An Evidence-Based Exposure Questionnaire for Interstitial Lung Disease: EXPO-ILD

Many interstitial lung diseases (ILDs) are associated directly or indirectly with inhaled environmental and/or occupational exposures; exposure identification is critical for diagnosis and clinical management. However, there are currently few evidence-informed exposure questionnaires for ILD, and none are in widespread systematic use. This study sought to develop an evidence-informed ILD exposure questionnaire, leveraging international expert-based consensus on exposures that present relevant risk for ILD development.

What environmental and occupational exposures are risk factors for the development of ILD and should be included on ILD-specific exposure questionnaires?

Participants with expertise in ILD, occupational respiratory medicine, or exposure assessment were invited to complete 2 rounds of a modified Delphi survey to identify relevant exposures associated with the risk of developing ILD. Items in the first Delphi round were informed by prior data, including a systematic review/meta-analysis and scoping review of questionnaires. Items not meeting consensus in the first round were carried over to the second round, with additional items added or modified as suggested by participants. Well-established causal exposures were not included. A priori definitions of consensus were applied, indicating response distribution.

A total of 38 of 43 experts (88%) participated in the Delphi survey, with 37 of 38 (97%) completing both rounds. A total of 11 exposures met consensus for agreement as relevant risk factors for ILD, whereas 9 met consensus for disagreement as being irrelevant to ILD risk. Six exposures did not achieve consensus. Incorporating these findings with prior evidence syntheses, we developed 2 exposure questionnaires (EXPO-ILD-Short and EXPO-ILD-Long) for ILD for application in both clinical and research settings.

This international modified Delphi identified clinically relevant exposures that are risk factors for ILD, based on expert consensus. Integrating with previously established findings, we developed evidence-informed exposure questionnaires. Implementation efforts should include content validation and assessment of performance characteristics in diverse settings.