Inclusion Criteria:  Age ≥ 16 years Spirometry indication Able and willing to use at-home spirometry  Exclusion Criteria:  On the discretion of the recruiting clinician if he or she deems a patient not eligible. Inability to understand and sign the informed consent form Known previous inability to perform spirometry Contraindications to perform spirometry as listed in the standardization of Spirometry 2019 update (Graham et al., 2019)