Radar plot of development stages per eNose and disease. Studies were divided into five different stages: (1) proof of concept study; (2) cohort size of diseased participants less than fifty; (3) cohort size of diseased participants equal or more than fifty; (4) study cohort with an external validation cohort; (5) evaluation of clinical implementation. The highest stage reached for each eNose per lung disease is displayed. eNose prototypes are not included. BIONOTE biosensor-based multisensorial system for mimicking nose tongue and eyes, CF cystic fibrosis, COPD chronic obstructive pulmonary disease, ILD interstitial lung disease, OSA obstructive sleep apnoea, PEN portable electronic nose.