SVC is obtained with in-clinic conventional spirometry, in-clinic portable spirometry, and in-home portable spirometry with respiratory therapist-supervised remote pulmonary function testing every two weeks in a six month prospective study of participants with a diagnosis of Amyotrophic Lateral Sclerosis. SVC decline over time, seated and supine, will be tracked with assessments for treatment changes.
The investigators seek to validate Slow Vital Capacity (SVC) measurement in seated and supine positions using conventional and portable spirometry.